Radio Doctor For Motorola Radius Gm300
Motorola Radius GM300 Radio Doctor for Windows 2000/XP & dOS,untuk SETTING radio Radius GM300 (2.1. You do this with the help of a Hex. Hex Workshop This can be found. The file you need to modify is. Jun 08, 2018 Radio Doctor for MOTOROLA RADIUS GM300 versi 1.3. To Hack Shopadmin Asp. Coba lagi download,mungkin servernya lagi down. Table 1 Rated Power and Distance Rated Power of Vehicle-Installed Minimum Distance from Mobile Two-Way Radio Transmitting Antenna 7 to 15 Watts 30.5 cm (1 Foot) 16 to 50 Watts 61 cm (2 Feet) More than 50 Watts. Radio Doctor for MOTOROLA RADIUS GM300 versi 1.3. To Hack Shopadmin Asp. Coba lagi download,mungkin servernya lagi down. Table 1 Rated Power and Distance Rated Power of Vehicle-Installed Minimum Distance from Mobile Two-Way Radio Transmitting Antenna 7 to 15 Watts 30.5 cm (1 Foot) 16 to 50 Watts 61 cm (2 Feet) More than 50 Watts. The GM300 was Motorola's next step in the MaxTrac / Radius mobile product lines. The schematics are remarkably similar. You can even interchange some boards between the GM300 and MaxTrac radios. Like the MaxTrac, the GM300 line has been discontinued by the manufacturer. I came across something in yahoo called Radio Doctor witch is. Motorola GM300 Programming - FJ45.COM FJ45.COM Tip on using the RPC-M300 '3 in 1' programming cable: I was inspired to create this page because I got a programming interface for a GM300 which came with no documentation.
- Motorola Radius Gm300 Radio
- Motorola Radius Gm300 Software
- Radio Doctor For Motorola Radius Gm300 Manual
- Motorola Radius Gm300 Radio Doctor For Windows 2000/xp
Maxtrac Index Motorola index Home page | Motorola GM300 Information Page By Robert W. Meister WA1MIK |
The GM300 was Motorola's next step in the MaxTrac / Radius mobile product lines. The schematics are remarkably similar. You can even interchange some boards between the GM300 and MaxTrac radios. Like the MaxTrac, the GM300 line has been discontinued by the manufacturer. Throughout this article, reference to MaxTrac radios implies Radius radios as well.
Naturally, you need different programming software (RSS), but if you've ever programmed a MaxTrac, you'll be right at home with the GM300. The radios operate the same, too. See below for more info on the RSS and programming.
GM300 mobile radios cover the VHF (136-174 MHz in two ranges) and UHF (403-520 MHz in four ranges) bands, with 8 or 16 channels, 12.5 or 20/25/30 kHz channel spacing, and 10, 25, and 35-45 watt power levels. They use the same accessories (loudspeakers, microphones, accessory plugs, power cords, mounting brackets, etc.) as the MaxTracs.
The M120 radio is just about the same as a GM300 but has 'less features' - this would be the 2-channel version, equivalent to a MaxTrac 50. There is also an M10 single-channel radio, and an M130 2-channel radio that is an M120 with the GM300's signaling capabilities.
The 16ch GM300 radio uses the expanded logic board with firmware in an EPROM, that gives you the ability to program several of the accessory jack pins. The 8ch GM300 and the M-series all use the masked logic board that has no programmable pins. The masked logic board also has limited code plug space, hence fewer channels and less capabilities.
Here's a front view photo of a 16-channel MaxTrac, a 16-channel GM300, and a 2-channel MaxTrac:
GM300 Model Numbers:
The first six characters are pretty much standard Motorola convention. The IF frequency is usually 45.1 MHz but if you have multiple radios near each other, this can cause interference, so you can optionally order the radio with an alternate IF frequency.
Mount | Power Watts | Band MHz | Series | I.F. MHz |
---|---|---|---|---|
M: dash | 0: 1-10 | 3: 136-174 | GM: ? | C: 45.1 |
3: 10-25 | 4: 403-520 | XQ: ? | R: 45.3 | |
4: 25-45 | XV: ? |
The XV-series seems to all be 1 channel radios. The XQ-series seems to be all 2 channel radios. The GM-series can be 2, 8, or 16 channel radios. The XV and XQ may be used by the M10, M120, and M130 radios.
The second six characters provide a lot of useful information about the capabilities of the radio and the boards contained within it.
Spacing kHz | # Ch. | Logic Board | Range MHz | Rev. |
---|---|---|---|---|
0: 12.5 | 0: 8 | C: Expanded | 1: 136-162 | A_ |
2: 20/25/30 | 9: 16 | D: Masked | 1: 403-430 | |
2: 146-174 | ||||
3: 438-470 | ||||
4: 465-490 | ||||
5: 490-520 |
A typical model number would be M44GMC09C3A_. This is a 40 watt, UHF radio, 45.1 MHz IF, narrow spacing (12.5 kHz), 16 channels, expanded logic board, 438-470 MHz band.
It is rare that the model number includes the specific frequency range the radio is capable of handling (10th character). You don't get that lucky with MaxTracs, Spectras, etc. I wish all the model numbering was so useful. It is NOT practical to change the frequency range for which the radio was manufactured. The RF board and PA assembly are frequency-dependent; the logic board and front panel are not. As the model number tells you which range the radio is, if you end up with the wrong one (assuming the radio hasn't been thrown together out of spare parts or had modules swapped) it's your own fault for not doing your homework.
The expanded logic board has its firmware contained in a socketed EPROM, which can be replaced. The masked logic board has its firmware permanently stored in the soldered-in microprocessor IC. People have apparently modified the RSS to get 16 channels from masked logic board radios and 40 channels from expanded logic board radios.
It would appear that GM300s are not capable of any form of trunking operation. However they can do G-Star signaling for use with GE radio systems.
There are other models, such as M10, that are often called GM300. This article is specifically oriented towards the radios with 'GMC' in the model number.
Specifications:
Click on the image to enlarge it.
Note that a revision to the service manual shows two VHF ranges: 136-162 MHz and 146-174 MHz. Also, the power levels are continuously variable throughout the three ranges: 1-10, 10-25, 25-45 watts.
Board Numbers:
This list is sorted alphabetically by Function, then Description.
Board # | Function | Description |
---|---|---|
HLN8075A | Display Board | |
HLN8070A | Logic Board | Expanded, 4-layer |
HLN8070D | Logic Board | Expanded, 4-layer |
HLN8074A | Logic Board | Masked, 2-layer |
HLN8074E | Logic Board | Masked, 2-layer |
HLE8385A | UHF Power Amp | 403-433 MHz, 01-10 Watts |
HLE8275A | UHF Power Amp | 403-433 MHz, 25-45 Watts |
HLE8267A | UHF Power Amp | 438-470 MHz, 01-10 Watts |
HLE8034A | UHF Power Amp | 438-470 MHz, 10-25 Watts |
HLE8271A | UHF Power Amp | 438-470 MHz, 25-40 Watts |
HLE8284A | UHF Power Amp | 465-495 MHz, 25-40 Watts |
HLE8269A | UHF Power Amp | 490-520 MHz, 25-35 Watts |
HLE8229A | UHF RF Board | 403-433 MHz, 25 kHz |
HLE8230A | UHF RF Board | 403-433 MHz, 12.5 kHz |
HLE8301A | UHF RF Board | 438-470 MHz, 12.5 kHz |
HLE8300A | UHF RF Board | 438-470 MHz, 25 kHz |
HLE8264A | UHF RF Board | 465-490 MHz, 12.5 kHz |
HLE8263A | UHF RF Board | 465-490 MHz, 25 kHz |
HLE8228A | UHF RF Board | 490-520 MHz, 12.5 kHz |
HLE8227A | UHF RF Board | 490-520 MHz, 25 kHz |
HLD8293A | VHF Power Amp | 136-162 MHz, 10-25 Watts |
HLD8299A | VHF Power Amp | 146-174 MHz, 01-10 Watts |
HLD8033A | VHF Power Amp | 146-174 MHz, 10-25 Watts |
HLD8287A | VHF Power Amp | 146-174 MHz, 25-45 Watts |
HLD8266A | VHF RF Board | 136-162 MHz, 12.5 kHz |
HLD8265A | VHF RF Board | 136-162 MHz, 25 kHz |
HLD8029A | VHF RF Board | 146-174 MHz, 12.5 kHz |
HLD8031A | VHF RF Board | 146-174 MHz, 25 kHz |
HLN8071A | Vol/Mic Board |
Logic Board Jumpers:
Click on any image to enlarge it.
The documentation page above lists the jumpers as JUnnn. For some reason these are shown on the board layouts as either Pnnn or JUnnn. They're the same thing. There may or may not be silk-screened legend on the boards; it depends on the revision level.
There are two quite different logic boards used with the GM300. One (the expanded logic board) has a shield over the microprocessor components, its program is stored in a socketed EPROM, and the board has four layers, while the other (the masked logic board) has all the components exposed, its program is stored within the microprocessor, and the board only has two layers. The image below shows the location of the jumpers on the two-layer (masked) board:
The image below shows the location of the jumpers on the four-layer (expanded) board.
These jumpers are quite visible on the photo of the expanded GM300 logic board below. Note that some of them are also present on MaxTracs and have the same functions.
Accessory Connector:
Click on the image to enlarge it.
Note that the 8-channel radio signals are slightly different than the 16-channel radio signals. That may be due to the masked vs. expanded logic board. Fortunately, you can use an accessory plug wired for a MaxTrac (7-9, 15-16) in a GM300.
Click on the image to enlarge it.
The accessory connector and pins are also well documented in the MaxTrac section.
Note that many accessory pins on the expanded (four-layer) logic board are programmable, whereas you're stuck with the pin assignments on the masked (two-layer) logic board and these can't be modified.
Channel Steering:
The 16-channel expanded logic board radios support 'channel steering' through the accessory connector. You need to program the general-purpose I/O pins (6, 8, 9, 12, and 14) for 'Channel Select'. They turn into a binary coded input that allows you to select any of the possible 16 channels by grounding the appropriate input lines (assuming you've programmed the radio for active-low inputs). To select channel 1, ground the 'Channel Select 1' line. Channels 1, 2, 4, 8, or 16 may be selected by grounding select line 1, 2, 3, 4, or 5 respectively. All other channels are selected by grounding multiple select lines. If you release all of these lines, the radio reverts to the channel selected by the front panel. If you select a channel that does not exist (i.e. 10 channels programmed and you select channel 16), the radio reverts to the channel selected by the front panel. Channel steering DOES work as expected on radios with more than 16 channels, i.e. you can select anything up to channel 31, as that's all that's possible with five select lines. This article tells you how to use channel steering.
Motorola Radius Gm300 Radio
Pins 4,8,12,14 can be configured for COR. Pins 6,8,9,12,14 can be configured for Channel Select. So you can put COR on pin 4 and CS on the others. The fact that the masked (8-channel) radios and most MaxTrac users selected pin 8 for PL&COR Detect is something that will have to be changed if you want multiple features activated. It's up to the user to choose the desired functionality given the number (six) of programmable I/O lines.
The Motorola Radius programming software also supports Channel Steering if you have Version 21.01 firmware in the radio and a 16-pin logic board. Unfortunately, the MaxTrac software does NOT offer this feature, so if you have a MaxTrac and you want channel steering, you have to install the Version 21.01 firmware, then blank and initialize the radio with RADMBL software, turning it into a Radius model, just so you can program the accessory connector to handle channel steering. Also, the Radius software only provides for three Channel Select input lines, not five like the GM300. This means you can only select channels 1 through 7 plus whatever the front panel has selected, regardless of how many channels the radio might be programmed with.
Programming:
The HVN8177 programming software (RSS) programs the M10, M120, M130, and GM300 mobiles, as well as the GR300, GR400, and GR500 desktop repeaters. The latest release is HVN8177F version R05.00.00 dated December 1995. The RSS is shipped on 3.5-inch diskettes and is a DOS-only program.
The microphone connector is exactly the same as on a MaxTrac, and it's also well-documented in the MaxTrac section. The programming cable and RIB setup is the same as what you'd use for a MaxTrac or GTX.
You can hex-edit the MDF file in the RSS to allow an 8-channel radio to take 16 channels. Additional information is available at Colin Lowe's web site.
The GM300 with the expanded logic board supports the same common signaling modes as a MaxTrac (PL, DPL, MDC, etc.).
Differences from a MaxTrac:
The GM300 has models that fully cover the 144-148 MHz and 440-450 MHz amateur bands. Some MaxTracs will go that low if you adjust the VCO and hex-edit the RSS.
The GM300 RF boards have a local/distant attenuator in the receiver front end. This reduces the gain of the receiver and improves intermod rejection by 10dB. You can put a GM300 RF board into a MaxTrac, but there will be no control of the local/DX circuit, and the radio will have poor sensitivity. The circuit can be activated by soldering a small jumper on the RF board. The GM300 RSS and logic boards know how to control this circuitry; the MaxTrac RSS and logic boards do not.
The GM300 control head is quite similar to the MaxTrac. There is an additional circuit board, soldered to the logic board pins, that the control head connectors plug into, that provides some RF filtering and Zener diodes to protect from excessive voltage. Also, the internal speaker now connects through the control head cables, rather than on its own 2-wire cable. This makes it easier to remote-mount a GM300. There are kits available for this purpose.
For comparison, here's the inside view of a MaxTrac. Notice the lack of shielding and no filter board between the logic board and control head.
The GM300 logic board is significantly different from the MaxTrac logic board. It can control the RF board's local/DX circuit. The audio power amplifier is one single IC rather than discrete transistors. The heat-sink is considerably different and mounts only to the bottom of the chassis - no more T8 flat-head screws through the side of the chassis. There are far fewer components on the board too. All GM300 logic boards have a 16-pin accessory connector. A full metal shield covers the entire logic board, just like they have for the RF board; the MaxTrac only shields the microprocessor area. This further reduces spurious emissions.
The GM300 audio amplifier drives both sides of the loudspeaker. Therefore you must NOT ground either pin 1 or pin 16 of the accessory connector. You must run two wires to an external speaker. The same circuit design and components are used on the Spectra radios and they suffer from the same restriction. Grounding either speaker lead may let out the chip's lifetime supply of smoke.
The internal loudspeaker for the GM300 (and MaxTrac/Radius) radios is p/n 5080085D03, however this part number has been replaced by p/n 5004639J01. This is a 22 ohm, 5 watt speaker that retails for around $7US in early 2009.
The GM300 power amplifier has a thermistor mounted near the final transistor, so it actually senses the heat-sink temperature. The logic board uses this to control the output power in a more reasonable way; the power will be reduced if/when the power amplifier gets hot enough, not when the microprocessor 'thinks' it's getting hot from extended use. This makes GM300 radios more suitable for repeater transmitter usage. (They still need adequate forced-air cooling.) This extra signal requires a 6-wire cable and connector between the PA and the logic board (the MaxTracs only have a 5-wire cable and connector). I have heard that you can use a GM300 PA in a MaxTrac by snipping the temperature sensor wire off the connector, but I personally would not butcher either the radio or the cable that way.
Blanking the Radio:
There doesn't seem to be a lab version of RSS for the GM300. You can fool RSS into thinking the radio is blank by manually erasing the serial number (filling it with spaces) and entering a few more bytes using the bit-banging facility available in the MaxTrac lab RSS program. After that, you should be able to initialize the radio using the GM300 RSS or write a previously saved code plug to the radio. Initialization is exactly the same as the steps you'd do for a MaxTrac: set the radio model number, frequency range, signaling features, panel number, serial number, key in the crystal data and 9.6V reading, and align the power amplifier and deviation circuits.
Note: people have used the MaxTrac lab RSS to blank GM300 radios. They then install a MaxTrac EPROM, make some changes to the logic board, and turn the radio into a MaxTrac, including the model number. Then they initialize it with MaxTrac RSS.
To blank the radio, you need to deposit the following data at the locations shown. These values came directly from a factory-fresh blank board. This data will go directly into the radio's memory. You may want to write down the contents of these locations first, incase something goes terribly wrong. Use this at your own risk. All values are hexadecimal.
Loc | Data | Usage |
---|---|---|
B600 | 20 | Serial # |
B601 | 20 | Serial # |
B602 | 20 | Serial # |
B603 | 20 | Serial # |
B604 | 20 | Serial # |
B605 | 20 | Serial # |
B606 | 20 | Serial # |
B607 | 20 | Serial # |
B608 | 20 | Serial # |
B609 | 20 | Serial # |
B60A | FF | Panel # |
B60B | FF | Model Index # |
B60C | 1B | Product # |
B60D | FF | SW Ver. |
B60E | FF | ??? |
B60F | 4F | ??? |
B610 | FF | ??? |
After setting the memory to these values, the radio will appear blanked to the GM300 RSS, and you'll have to go through the blank board replacement procedure and either align the radio, or fill in the various fields with data that was previously there. You can also write any previously saved code plug to the radio, but make sure you use one that matches the band and number of modes.
During the first screen of the initialization procedure, you'll need to select the frequency range. Go through the entire list using the up-arrow, then go through it a second time to find the exact range. Once the correct range is chosen, you'll have no problem choosing a model number. If you don't see the expected range, go through the entire list again.
By the way, the RSS knows about two 'panel numbers' for these radios: 005 for the multi-digit (8/16 channel) radios, and 004 for the other (1/2 channel) radios, and it covers the Radius GM300, M10, M120, and M130 models.
The value at location B60C is an entry number of the Product Series in the MDF file. There are only four possible values and you must select a value for this location. The value at location B60F seems to depend on which logic board is in the radio. There's a checksum at location B611 but don't bother with it. The table below shows the values that can go into these two locations. All values are hexadecimal.
Product Series | Logic Board | #Ch | B60C | B60F |
---|---|---|---|---|
Radius GM300 | Expanded | 16 | 1B | 4F |
Radius GM300 | Masked | 8 | 1B | 45 |
Radius M120 | Masked | 2 | 20 | TBD |
Radius M10 | Masked | 1 | 21 | TBD |
Radius M130 | Expanded | 2 | 29 | TBD |
You should always record the original values or make a backup when hex-editing any radio or file.
Common Problems:
Motorola Radius Gm300 Software
For some reason, GM300s seem to be prone to losing receive sensitivity. Whether this is due to nearby excessive transmitter power or operator error, the eventual cause seems to be either shorted protection diodes across the receiver's input, or a dead first RF amplifier transistor. All of these components require removal of the RF board to access them, but replacement is quite easy. They're surface-mount, of course.
Another common issue is a dead 2nd oscillator crystal. This operates at 44.645 MHz and is used to convert the 45.1 MHz intermediate frequency signal down to 455 kHz for the detector. When the crystal dies, the receiver will hear absolutely nothing. If you have a receiver capable of hearing the crystal frequency, you can pick it up if you remove the shield from the RF board and place the antenna within a few inches of the left side of the radio. If you don't hear the 44.645 MHz signal, the crystal needs to be replaced. These can often be found on a popular auction web site. The Motorola p/n is 48-80008K02 and the crystals are marked '44.645/08K02' so you know they're the right ones.
These radios often go way off frequency, to the point that the warp adjustment will not get it back where it belongs. The cause is most often dirty interconnection pins inside the radio. These are between the RF board and the logic board. On the MaxTrac, they are attached to the logic board; on the GM300 the strip of pins is mounted on the chassis and both boards plug into it. Remove both boards, clean these pins, and reinstall the boards. While the radio is apart, clean the front panel connectors too. These same connectors get dirty on MaxTracs as well, but for some reason they don't often cause serious problems like they do on the GM300. See this article for details and photographs.
Reference Oscillator Coarse Adjustment Procedure:
Rather than type this paragraph, here it is directly from the service manual. This same procedure (with different part references) could also be used with MaxTrac radios.
Manuals and RSS:
- GM300 8-channel Operator's Card, 6880902Z26
- GM300 16-channel Operator's Card, 6880902Z41
- GM300 Owner's Manual, 6880902Z09
- GM300 Service Manual, 6880902Z32
- GM300 RSS, HVN8177F
- GM300 RSS Manual, 6880902Z36
Acknowledgements and Credits:
Dave N1OFJ supplied the GM300 and MaxTrac 50 radios. These photos were taken at his shack.
All photographs were taken, and are copyright, by the author.
Much of the information for this article, and the scanned pages, were obtained from the official Motorola GM300 Service Manual.
A few tidbits of information were gathered from Internet sources.
GM300, MaxTrac, Radius, RSS, PL, DPL, MDC, and probably a bunch of other things, are trademarks of Motorola, Inc.
Contact Information:
The author can be contacted at: his-callsign [ at ] comcast [ dot ] net.
Back to the top of the page
Maxtrac Index
Motorola Index
Back to Home
This article first posted 28-Sep-2006.
This page was last updated on 06-Dec-2015
This web page, this web site, the information presented in and on its pages and in these modifications and conversions is © Copyrighted 1995 and (date of last update) by Kevin Custer W3KKC and multiple originating authors. All Rights Reserved, including that of paper and web publication elsewhere.
Up one level Back to Home | The Motorola MaxTrac, Radius, GM300, DeskTrac, GR-series Index page Maintained By Robert Meister WA1MIK This page has undergone a major reorganization. Everything is all still here; items just got moved. Use your browser's SEARCH function to find things, as they're now sorted better. |
Radio Doctor For Motorola Radius Gm300 Manual
Attention Ebay buyers and sellers: If you are buying or selling a MaxTrac, Radius mobile, or GM300 you need to read the warning on this page.
Any Motorola prices mentioned on this page (or on any page at this web site) should be taken only as a rough guideline. Motorola adjusts prices quarterly, and offers one set of prices to their dealers/service shops (the so called 'NSO' Pricing ('National Service Organization')), another to 'self-maintaining' fleet customers (i.e. those that have their own radio shops... cities, counties, police departments, fire departments, etc) and a third on their telephone order desk (i.e. retail sales to the public). Prices are changed quarterly, so use the mentioned prices only as a rough indication. If you encounter a large price change on anything where we've mentioned a price we'd appreciate an emailed update.
Radio Modification and Descriptive Articles:
Caution: A lot of the information in the articles below is valid only for MaxTracs and MaxTrac-based Radius radios (the Radius mobiles that have the letters LRA in the middle of the model number). The MaxTracs came first, then when Motorola needed radios to sell as Radius models (i.e. retail sales products) they changed the label and the firmware. There are some very slight differences, but there is a lot of commonality between the hardware (the circuit boards, etc) inside the MaxTrac and Radius LRA series mobiles.
The later GM300 series (which includes the Radius M10, M120 and M130 radios) look a lot like the MaxTrac and Radius LRA series, have similar specifications and physical construction, but are actually quite different internally. The GM300 series do not respond well to being blanked by the MaxTrac Lab RSS. There is no Radius or GM300 series Lab RSS floating around (yet) so unsuspecting experimenters can turn one of these radios into an expensive brick if not careful. See the GM300 article below for more details.
Astron makes a power supply for the MaxTrac / Radius LRA / GM300 series that has a sleeve on the top that the radio slides into. The SL-11-RRA supplies 13.8V at 11 amps. Click here for a photo.
Note that the MaxTrac / Radius / GM300 radios have a 10% transmit duty cycle and that translates to 10 seconds of transmit and 90 seconds of receive, or 30 seconds of transmit and 4.5 minutes of receive. This is definitely not repeater service or any kind of amateur radio service that I'm familiar with! And besides, the rear mounted heat sink does not cool the pin diodes or any other PC-board mounted components. Reducing the transmit power can help, but some models have a minimum rated power level (like not less than 25 watts and not more than 45 watts). In other words, the MaxTrac, Radius and GM300 are nowhere near the conservatively rated and over-heat-sinked designs of the MICOR, Syntor or Mitrek era radios.
Introductory Information on the MaxTrac, Radius and GM300 series radios, the DeskTrac station, and the GR300, GR400, GR500, GR1225, R1225 and RKR1225 series repeaters Compiled by Mike Morris WA6ILQ An introduction to the Motorola radios covered by this section, with background, history, some model-specific information, photos, and lots of miscellaneous tidbits such as mic jack or antenna connector replacement. You should read this article before any of the other articles here. |
An Introduction to the MaxTrac or Radius M100 / M214 / M216 Firmware, Logic Boards and RF Boards By Neil Johnson WBØEMU What your radio can do depends a lot on what version firmware you have in which logic board mated to which RF board. |
Identifying the five most common Radius models By Bob DeMattia K1IW Some front panel images with text that describes the major differences. |
MaxTrac Logic Board Jumpers and Connectors By Robert Meister WA1MIK Locations and explanations of the three-pin jumpers on MaxTrac and Radius logic boards, as well as the signals on the three multi-pin connectors. |
The Definitive Guide to the 16 pin MaxTrac and Radius Option Connector By Neil Johnson WBØEMU Not every output pin or input pin is equal... Some are more equal than others... |
Transmitter Spurious Outputs when runat less than rated power By Robert Meister WA1MIK The myth about running radios at less than rated output power: confirmed, plausible or busted? The author does some simple experiments and analysis. |
That annoying 'cli-click' when the PTT button is released By Robert Meister WA1MIK Some radios do it, some don't. The author traced the source and shows severalways to get rid of it. |
Microphone Hang-upMechanisms By Robert Meister WA1MIK A primer on hang-up buttons found on MaxTrac mikes, but the same schemes areused by a lot of other Motorola radios, and some similar schemes are even usedon radios made by other manufacturers. |
Self-Quieting Frequencies Compiled by Robert Meister WA1MIK GM300, MaxTrac, Radius, and MaraTrac mobile radios all share designs and components, so they all suffer from this problem. Here's a collection of frequencies that these radios can generate internally; some of them can be annoying. |
Model-Specific Articles:
Overview of the DeskTrac Station By Robert Meister WA1MIK Model numbers, connectors, interface signals, front panel overview, photographs. A lot of the information came from the DeskTrac Service Manual. |
Information about the GM300-series radios By Robert Meister WA1MIK Specs, board numbers, accessory plugs, how they differ from MaxTracs. |
MaxTrac VHF, UHF, and 800 MHz radio models By the Repeater-Builder Staff Information taken directly from the 'No Longer Available' detailed service manual. |
MaxTrac 900 MHz radio models By Repeater-Builder Staff Information taken directly from the 'No Longer Available' service manuals. |
Radius M100, M206, M208, M214, M216 radio models and board info Compiled by Robert W. Meister WA1MIK Information extracted from the Radius Service Manual (of course NLA). |
A reproduction of the MaxTrac Performance Specifications 20KB PDF file |
MaxTrac initialization programmingchoices By Robert Meister WA1MIK A follow-up to the article below that details the once-only screen fields you must fill in when initializing a radio. |
Hex-editing the 900 MHz MaxTrac MDF file by Robert Meister WA1MIK This article describes the process that you have to do so you can easily program your MaxTrac on amateur 900 MHz frequencies. You can find it in the Motorola RSS and RIB articles section of this web site. |
MaxTrac Secrets By Robert Meister WA1MIK Communications, code plug, and other internal data secrets of the MaxTrac-series radios. |
How the MaxTrac Controls Transmit Power and Deviation By Robert Meister WA1MIK An explanation of why the radio has weird transmit power and deviation on amateur frequencies and what you can do about it. Applies to GM300, Radius, and MaraTrac radios too. |
Ham-friendly Firmware Mods for the MaxTrac By Robert Meister WA1MIK What to change in the firmware to deal with out-of-band operation. A follow-up to the article above. Applies to Radius and MaraTrac radios too. |
How to replace the firmware and what to align for the MaxTrac By Robert Meister WA1MIK The procedure to replace the firmware chip and what needs to be realigned when doing so. A follow-up to the article above. Applies to Radius and MaraTrac radios too. |
MaxTrac Adjustments By Robert Meister WA1MIK More than you ever wanted to know about the various pots and coils on the RF boards of the MaxTrac-series radios, and how to adjust them. Of course Motorola doesn't want you to twiddle with these, but occasionally it's necessary. |
Replacing the Dallas Memory Module In the MaxTrac or Radius By Scott Withrow KC9LQV Radios that use the Dallas NVRAM will be losing their memory when the battery goes dead. They have about a 20 year lifetime, so any radio made prior to about 1992 will have this problem and the Dallas chip will need to be replaced. This article tells you what to do about it. |
Some additional GM300 information is available from Colin Lowe G1IVG at http://www.g1ivg.com/motgm300.htm (offsite link).
Interfacing Articles:
Repeater controller interfacing - with photos By Scott Lichtsinn KBØNLY With information on connections to radios with both 16-pin and 5-pin logic boards. |
Simple Repeater Interfacing forMaxTrac / Radius / GM300 Radios By Robert Meister WA1MIK A very simple procedure with all the details needed to interface these radios to most repeater controllers. This is a companion article to the ones above and below. |
Repeater Interface for two radios 207 kB PDF Using a ID-O-Matic II kit, by Dale NØXAS, that has both a CW ID and a Time-Out/hang timer to make a repeater using MaxTrac, Radius, GM300, or CDM-series mobile radios. |
Using a MaxTrac / Radius / GM300 Mobile Radio as a CW Beacon Transmitter By Robert Meister WA1MIK The HamGadgets ID-O-Matic had all the features necessary for this task. It was just a matter of finding a way to transmit real on/off CW rather than modulated audio CW for beacon use. Should also work with the MaraTrac radios. |
Using Remote Channel Select on a 16-channel GM300 radio By Robert Meister WA1MIK A transcription of a PDF file with additional information that explains the wiring and radio configuration you need to remotely select channels on the 16-channel GM300 radio. This won't work on the 8-channel GM300 because the firmware won't allow you to reprogram the accessory connector pins for this purpose. |
Modification and Repair Articles:
Diagnosing, Troubleshooting, and Repairing MaxTrac Radios By Robert Meister WA1MIK Hints and helpful suggestions for repairing MaxTrac, Radius, and GM300 mobile radios. |
Disassembling the GM300 Mobile Radios By Robert Meister WA1MIK If your GM300 is way off frequency, this is usually caused by dirty interconnect pins between the logic board and the RF board. You'll need to take it completely apart to clean them. Here's a procedure for doing it. |
Narrow-band conversion kits for the GM300-series radios By Robert Meister WA1MIK Transcribed from the official document that can be found elsewhere on this site. |
Adding additional channels to the GM300 By Thomas M. Mayse, KN5S If your GM300 has the expanded logic board it can have as many as 40 channels. Moto learned their lesson on the 32-channel MaxTrac and artificially limited GM300 to 16 channels so that they could force anyone needing more than 16 into a Spectra. Tom walks you through the process with a step-by-step procedure. |
Upgrading a MaxTrac or Radius M100 / M214 / M216 to 32 channels - with photos By Scott Lichtsinn KBØNLY A step-by-step procedure that will upgrade any MaxTrac (except the 2-channel ones) to 16 or 32 channels (depending on which logic board you have), with options like scan. |
Additional Notes on MaxTrac or Radius M100 / M214 / M216 Logic Boards By Scott Lichtsinn KBØNLY This article goes with the 'Upgrading' article above. It has additional notes including a procedure for converting a trunking logic board to conventional. |
Moving a 449-470 MHz MaxTrac to cover the 440-450 MHz Amateur band - with photos By Scott Lichtsinn KBØNLY A step-by-step procedure that makes a UHF MaxTrac a lot more useful on 440-450 MHz. |
Manual Power Control of the MaxTrac PA deck By Robert Meister WA1MIK When a MaxTrac (on any band) is run out of it's designed frequency range the power control routines in the firmware get confused. Unfortunately the confusion causes the radio to run the PA deck wide open, which can burn it up. This writeup gives a workaround. |
Volume Control Replacement By Robert Meister WA1MIK If you have a MaxTrac, Radius LRA or GM300 series radio that runs at full volume all the time, or either turning the volume control has no effect or causes a huge jump in volume, then you have a broken volume control (a common problem). It's a simple, inexpensive fix and this writeup walks you through the repair. |
Volume Control Replacement UPDATE By Robert Meister WA1MIK The original and new Motorola pots are No Longer Available but an alternate part can be purchased for about the same price that does the job quite well. |
A Squelch Mod for the MaxTrac / GM300 / M120 By Barry Sloan VE6SBS Barry's web siteOriginal offsite article This simple mod minimizes the squelch tail duration - a useful feature on consistently strong signals (such as on point-to-point links). And if you want, you can add a switch to make the modification selectable at will. Just add a toggle switch in series with the lead of the capacitor. |
Converting an 800 MHz talkaround MaxTrac to a 902 MHz Repeater Receiver By Robert Meister WA1MIK An 800 MHz MaxTrac mobile with the talk-around option makes a good 902 MHz link, control or repeater receiver. This writeup walks you through the process. |
Converting Other 800 MHz MaxTracs to the 900 MHz Ham Band By Robert Meister WA1MIK A continuation of the above article based on followup information. |
Replacing the front-end filters in 800 and 900 MHz MaxTracs By Robert Meister WA1MIK This article describes how to cleanly remove and install new front-end filters in these radios. A companion article to the ones above and below. |
Extending the MaxTrac 900 MHz VCO Frequency Range By Robert Meister WA1MIK andDavid Malicki, N1OFJ How to move the 900 MHz MaxTrac VCO down to 902 MHz. |
Getting the MaxTrac 900 MHz radio to fully cover 902-928 MHz By Robert Meister WA1MIK An expansion of the articles above and below, with detailed analysis. Also shows a way of adding a manual deviation control if your radio needs it. |
Changing the MaxTrac 900 MHz VCO switch point By Robert Meister WA1MIK The MaxTrac 900 MHz radio's VCO has two ranges. This article explains why, and shows how to change the frequency where the range is switched. This will extend the useful operating range of the transmitter. |
Converting a 900 MHz MaxTrac from Trunking to Conventional operation By Robert Meister WA1MIK Replacing the firmware, blanking the board, and complete initialization steps. |
Converting a 900 MHz MaxTrac from Trunking to Conventional operation - An Alternate Method By Greg Stahlman KJ6KO This article assumes that you have read the article above first. |
Converting a 146-174 MaxTrac or Radius to 220 MHz By Matt Krick, K3MK Yes, you CAN move a VHF MaxTrac or Radius LRA to 220 MHz, complete with direct frequency entry in the RSS. This is NOT a beginners project, it requires serious surgery, access to a milling machine, and is best done to a radio that has a blown up PA deck. |
Converting a low-band MaxTrac to Six Meter Operation By Robert Meister WA1MIK All of the steps necessary to make a 42-50 MHz radio operate in the 46-54 MHz range. Two radios were converted; the trials and tribulations, plus the results, are summarized here. |
The Ontario Hydro Low-band MaxTrac 99-Channel Conversion By Robert Meister WA1MIK Documentation and procedure for converting a 42-50 MHz low-band radio. |
Permanently Disabling the Extender on a Low-band MaxTrac Radio By Robert Meister WA1MIK A simple jumper disables the noise blanker. This is necessary for radios that will be used as base station or repeater receivers. |
MaxTrac Transmit PL Mute Circuit By Robert Meister WA1MIK A simple circuit that immediately mutes the transmit PL tone. Especially helpful on radios that don't have a 16-pin accessory jack. |
Converting a MaxTrac 146-174 MHz radio to 136-162 MHz for APRS use By Robert Meister WA1MIK Some MaxTracs work on 144.39 MHz; others do not. Bob analyzed the radio's performance on both range splits and tells you what needs to be done to improve operation below 146 MHz. This was suggested by Scott KBØNLY who modified a bunch of radios in his area for APRS. |
Getting a Line Output signal from a MaxTrac radio By Robert Meister WA1MIK Often, MaxTracs are used to monitor police and fire calls in garages and fire departments. These are usually noisy environments and amplifiers and loudspeakers are installed to boost the signal. As always, there are multiple methods of interfacing to MaxTracs, but by far the hardest unit to use is the one with the 5-pin accessory jack. Here's a fairly painless way to get the desired signal out of such a radio. Step-by-step instructions are provided so even a technician who's unfamiliar with the radio can make it work. |
Adding a Flat TX Audio Input to a 5-pin MaxTrac or Radius By Robert Meister WA1MIK Only the radios with 16-pin logic boards have a flat TX audio input. Three extra components give you the same functionality on 5-pin logic boards. |
Getting Discriminator Audio from a 5-pin MaxTrac radio by Scott Withrow, KC9LQV MaxTrac and Radius mobiles with 5-pin accessory jacks are often overlooked because they lack signals such as discriminator (flat) receiver audio. Scott duplicated the circuitry from a 16-pin radio and added it to his 5-pin radio to get flat audio out of it. This article shows what he did. |
Why the receive audio is lower on some MaxTracs than others by Robert Meister WA1MIK Analysis of the circuit and component value measurements solve this mystery. |
Maxdroid: Add a digital display and front-panel frequency selection to VHF/UHF MaxTrac transceivers By Avinoam Albo, 4X1HF (offsite link) |
Manuals and Documentation: If anybody wants to contribute additional part numbers (or even manual scans) we will post them.
Motorola Radius Gm300 Radio Doctor For Windows 2000/xp
FLN6433B MOSCAD Adapter for MaxTrac and GM300 68 kB PDF file Drawn by Eric Lemmon WB6FLY The RJ45 pin numbering is identical to the MIC jack convention used on those radios. | ||||||||||
FLN6746B IRRINET Adapter for MaxTrac and GM300 64 kB PDF file Drawn by Eric Lemmon WB6FLY The RJ45 pin numbering is identical to the MIC jack convention used on those radios. | ||||||||||
TLN5277E DC Power Line Filter Kit 214 kB PDF This is the alternator whine filter that Moto sells you for the MaxTrac, Radius, GM300, CDM series mobile radios. | ||||||||||
GM300 User Manual 6880902Z09 1.37 MB PDF file Early version manual, covers both 8 and 16 channel units. | ||||||||||
GM300 8-Channel Quick User Guide 6880902Z26-A 56.6 kB PDF file | ||||||||||
GM300 16-Channel Quick User Guide 6880902Z41-B 58.3 kB PDF file | ||||||||||
GM300 Accessories Brochure 743 kB PDF file | ||||||||||
GM300 Radio Service Software Manual 6880902Z36-B 2 MB PDF file | ||||||||||
GM300 Detailed Service Manual 6880902Z32, was about $13 (No Longer Available as of June 2007) This service manual covers the GMC and GMR models of the GM300 radio. This is another one you want on your shelf. You occasionally see these on popular auction sites. Note that this manual is not as well-organized as the MaxTrac Service Manual.
| ||||||||||
GR300 and GR500 Service Manual 6880903Z42-A 9.31 MB PDF This manual covers: a) the GR300 and GR500 housings, b) the fan assemblies, c) the power supplies (GR300=HPN8393, built by Astron and GR500=HPN9005, built by StarWerks), d) the HLN3948 Basic Controller, the HLN8389 Zetron ZR320 ('Selective Calling Repeater Controller'), the HLN8390 Zetron ZR330 ('Remote Telephone Interface'), the HLN9119 Zetron ZR340 ('Tone Remote Adapter Repeater Controller'), the HLN9004 Instrument Associates i50R ('Basic Interconnect RepeaterController') and HLN9121 TRA100R ('Advanced Interconnect Repeater Controller'). There is also some info in this manual about the R*I*C*K controller. This manual does not cover the HLN9447 Instrument Associates i20R, the HLN9120 i750R or the HLN8388 Zetron ZR310 (community repeater controller), however the ZR310 service manual is available for download from the Zetron page at this web site. There are two manuals that cover the i20R: The Service Manual 6880904Z40 and the Programming Manual 6880904Z55. As of March 2012 both are still in print and being sold by Motorola Parts. The Service Manual costs about $26, and theSoftware Manual costs about $32. And you will still need the i20R RSS, which is HVN9085. The i750 used HVN9084 and cable HLN9102A. | ||||||||||
GR300 and GR500 Controller Programming Manual 6880903Z43-A 5.51 MB PDF This manual covers the programming of the HLN3948 Basic Controller, the HLN8389 Zetron ZR320 ('Selective Calling Repeater Controller'), the HLN8390 Zetron ZR330 ('Remote Telephone Interface'), the HLN9119 Zetron ZR340 ('Tone Remote Adapter Repeater Controller'), the HLN9004 Instrument Associates i50R ('Basic Interconnect Repeater Controller') and HLN9121 TRA100R ('Advanced Interconnect Repeater Controller'). There is also some info in this manual about the R*I*C*K controller. | ||||||||||
GR400 and GR500 X-Pand Repeater Service Manual 6880905Z54-O 50 MB PDF This manual also contains SMRs for the HPN9005 and HPN9041 power supplies (schematics), and Troubleshooting for External Controllers. | ||||||||||
GR400 X-Pand Repeaters Battery Revert Accessory HLN9455 1.6 MB PDF file | ||||||||||
MaxTrac 100 and 300 User Manual 6880901Z04 389 kB PDF file | ||||||||||
MaxTrac Detailed Service Manual 6880102W84, was about $30 but is no longer available (NLA). This is the low band, high band, UHF, and 800 MHz MaxTrac service manual that covers the MGA, MJA, MQA, MWA and AHA models. If you ever pop a cover on any of those models then you want this book on your shelf; it's chock full of good stuff. You occasionally see these books on eBay and the other auction sites.
| ||||||||||
MaxTrac 900 MHz Service Manual 6802980G40 7.7 MB PDF. This is the 900 MHz MaxTrac Conventional service manual (the 900 MHz MaxTrac trunked radio service manual is part number 6802977G10). This manual deals with the 12w radios. It also has the info on the HMN1038A desk microphone and the HLN5309A 'Desk Tray' - the plastic base station stand that holds the radio in a comfortable position for use. If you have the 30 watt radio you need the supplement below. Other than the test modes, this manual covers the trunking models as well. You occasionally see these manuals on eBay and other auction sites. By popular demand, this manual was donated by Bob WA1MIK and scanned by Eric WB6FLY. | ||||||||||
MaxTrac 900 MHz 30 watt Power Amplifier Supplement IMR200 597 kB PDF. This is the 30 watt Power Amplifier Instruction Manual Revision (supplement) that came with a 6802977G10 Trunking Service Manual. It applies to conventional radios as well; the only difference is the firmware and front panel escutcheon. Note that the 30w model is rated for 30w on 896-902 MHz (i.e. the repeater input range) but only 20w on the talk-around / simplex 935-941 MHz range. This manual was donated by Bob WA1MIK and scanned by Eric WB6FLY. | ||||||||||
Changing a Radio's Personality Section 3 from a MaxTrac RSS manual 45 kB PDF This is close enough to be used for the GM300 and even the MaraTrac. | ||||||||||
Programming Advanced Features Section 4 from a MaxTrac RSS manual 177 kB PDF This is close enough to be used for the GM300. | ||||||||||
Alignment and Calibration Section 5 from a MaxTrac RSS manual 206 kB PDF This is close enough to be used for the GM300 and some applies to the MaraTrac. | ||||||||||
Radius (GM300) M10 User Manual 6880903Z05 1.34 MB PDF file | ||||||||||
Radius (GM300) M10 Service Manual 6880903Z03, about $28. This covers the XVC series of radios, a single-channel Radius GM300 that uses the 8-channel masked logic board. | ||||||||||
User's 'cheat sheet' for the Radius (GM300) M10, M120 and M130 6880902Z96. Save your money, if you have an IQ higher than that of egg white, you don't need this. | ||||||||||
Radius (GM300) M120 User Manual 6880902Z97 1.33 MB PDF file | ||||||||||
Radius (GM300) M120 Service Manual 6880902Z98-O 7 MB PDF Donated by Eric Lemmon WB6FLY This is a 2-channel Radius GM300 that uses the 8-channel masked logic board. The manual includes revisions MMR-077, MMR-100, and MMR-104. | ||||||||||
Radius (GM300) M130 User Manual 6880903Z64 1.29 MB PDF file | ||||||||||
Radius (GM300) M130 Service Manual 6880903Z65, about $30. This is a 2-channel Radius GM300 that uses the 16-channel expanded logic board. | ||||||||||
Radius M100, M208 and M216 User Manual (early) 6880901Z47 770 kB PDF file While the title page says M100 and M200, there never was a M200 model... this book covers the M100, M208 and M216. The later book is 6880900Z45. The M206 became the M208. The M214 became the M216. | ||||||||||
Radius M100, M206, M208, M214 and M216 VHF / UHF / 800 Service Manual 6880101W58-A 7.55 MB PDF This manual was about $45 when it was available and is the manual that covers all of the Radius LRA series except for the low band and 403-430 MHz radios. Low band and low range UHF were added in the revisions. I've never seen a 900 MHz Radius LRA. A large number of the board diagrams and service section of this manual are the same as the MaxTrac Detailed Service Manual. You need to include all of the Instruction Manual Revisions below into the manual. All of them include revised model tables.
| ||||||||||
Radius R1225 Transceiver Service Manual 6880905Z53-O 57.7 MB PDF file This is the radio that's used in the GR1225, GR400, and GR500 X-Pand repeaters. The manual also contains several SMRs. | ||||||||||
Radius RKR1225 Rack Mount Repeater Service Manual 6880907Z10-O 15.7 MB PDF file This repeater uses the R1225 transceiver. | ||||||||||
Instrument Associates was bought out by GAI-Tronics Corp. Reading, PA. They are at 800-492-1212. |
Parts Catalogs:
The MaxTrac Parts Catalog 2.2 MB PDF file |
Another MaxTrac Parts Catalog 200 kB PDF file |
A Radius M10 / M110 / M120 Parts Catalog 200 kB PDF file |
A Radius M208 / M216 Parts Catalog 200 kB PDF file |
The Radius GM300 Parts Catalog 200 kB PDF file |
Back to the top of the page
Up one level (Moto index)
Back to Home
This page originally posted 05-Jan-2005
Credits and Acknowledgements:
MaxTrac, Radius, GM300, Spectra, GT, GTX, GR300, GR400, GR500, Hear Clear, Radio Service Software, RSS and many other names are trademarks of Motorola Inc.
Front-view photos of the two-channel and multi-channel radios at the top of the pageby Robert Meister WA1MIK.
Edited text, artistic layout, and the hand-coded HTML is ©Copyright 2005 and date of last update by Mike Morris WA6ILQ.
This web page, this web site, the information presented in and on its pages and in these modifications and conversions is © Copyrighted 1995 and (date of last update) by Kevin Custer W3KKC and multiple originating authors. All Rights Reserved, including that of paper and web publication elsewhere.