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Compiled by Mike Morris WA6ILQ 		  Print this Page



Photo 1: A dual receiver wireline controlled MSR2000 continuous duty station.
The exciter and receiver card(s) are behind the panel above the horizontal cards.
The empty horizontal slot at the top left is for the "coded squelch" card (either PL or DPL).
The rightmost (double wide) vertical card is the line driver, the card to the left of it is the station control card.
The three cards in the center are usually used only in tone controlled wireline systems.
Click on the image above for a larger image (576KB).   Photos by Tim Ahrens W5FN



Photo 2: A view of the exciter and receiver card(s). From the left is the exciter, the second receiver and the primary receiver.
Most MSRs do not have the second receiver, and would have an empty center horizontal slot.
Both a single receiver base station and a repeater station will usually be missing the connector for the second receiver.
There are at least two different backplanes used - there is one for simplex and another for duplex.
Click on the image above for a larger image (457KB).   Photos by Tim Ahrens W5FN


This page is a work in progress... Your help is needed.   If anyone would like to contribute photos of the missing exciters and receivers (see the table below), or internal photos of the intermittent and continuous duty PA decks, or internal shots of the different power supplies, we'd appreciate them.
Remember, these pages are what YOU make of them.


The MSR2000 is a base or repeater station that was a follow-on to the Micor line, and was available only in high band VHF and UHF. It is basically a second-generation Micor station control shelf mated to the receiver and exciter sections of a Mitrek mobile, mated to a Micor-derived PA deck.   The station shelf has a few upgrades (like the horizontal slots at the top, and a new, more reliable style of card-to-backplane connector), and the RF sections are separate receiver and exciter sections. The control card cage is almost identical to a Micor and most of the notes on the Micor station control shelf are applicable. If you replace the card edge connectors that mate with the Micor backplane with ones made for the MSR you can use several of the Micor cards in the MSR card cage - BUT NOT ALL.   Compare the function of each pin before you go to the trouble of changing the connectors.

The MSR2000 is a non-synthesized station, and uses receiver and exciter modules that are derived from the Mitrek mobile radio.   The frequency-determining component is a self-contained oscillator-tripler plug-in module called a Channel Element, and there is one element for the receiver and a separate one for the exciter.   When you move an MSR from one frequency to another it requires swapping the Channel Element for one on the new frequency, or changing the frequency of the Channel Element by replacing the internal crystal with a new crystal for the new frequency.   This article is worth reading: Why should you really should spend $50 to re-crystal a channel element.

A list of the various channel elements used in the MSR station and the Mitrek mobile is here: Channel elements for the Mitrek and MSR2000.

The documentation for the MSR station consists of two separate manuals, and a full list is below. You will need to acquire a "Control and Audio" manual (which covers everything that is not frequency dependent) and an RF manual (that is frequency band dependent).   At the time of this writing (mid 2009) all of the RF manuals were out of stock (but are PDF'd below) and the "Control and Audio" manual was still available for US$55-$60.   Unfortunately a mistake was made inside the Moto publications group and the power supplies and accessories were included in the VHF RF manual instead of the Control and Audio manual, so if you have a UHF station you will need to print the power supply and accessory section from the high band PDFs below, or locate a VHF book just for the power supply and accessories.   Click here for instructions on how to order manuals.

As far as I can tell from the manuals, the model number structure on the USA-built MSR2000s breaks down as:

Sample model number: C74GSB-3106BTX         Numbers in [ ] refer to notes below.
C 7 4 G S B
Cabinet
Type [1]		 Power
Level		 Frequency
Band [2]		 Duty
Cycle [3]		 Configuration [4] Supply
Voltage [5]
B
Base
Station
Cabinet		 5
40-70 watts		 3
VHF		 G
Intermittent		 R
Base Station
(no duplex shield kit,
has the base station backplane)		 A
+12vDC
(rare)
C
Compact
Cabinet		 6
70-90 watts		 4
UHF		 K
Continuous		 S
Repeater
(has the duplex shield kit
and duplex backplane)		 B
120vAC
N
No
Cabinet		 7
90-120 watts		 K
120v or 240vAC

Sample model number: C74GSB-3106BTX         Numbers in [ ] refer to notes below.
3 1 0 6 B T X
Squelch
Type [6]		 Channel
Deviation [7]		 Frequencies [8] Control [9] Hardware
Version		 Configuration [10] (?) [11]
1
Carrier		 0
15 KHz		 0
Single Frequency		 3
Local Only		 A A
(?)		 X
(?)
3
PL		 1
5 KHz		 3
Two Frequency		 5
DC Wireline		 B B
Base
6
DPL		 9
Four Frequency		 6
Tone Wireline		 C D
(?)
7
(?)		 D T
Repeater
Table Notes:

  1. An "N" is a very rare beast, as they were special order. It was actually cheaper (and quicker) to order a "C" model and remove it from the cabinet (which could be sold to someone else). The factory "N" models were configured for open frame relay racks and use several different mechanical parts than those that were built for cabinet racks, and not all of those parts are covered in the manuals.
  2. The frequency range (the "split") is not encoded into the MSR2000 model number. To determine if you have a (for example) 132-150 MHz or a 146-174 MHz station you will need to look at the part number of a frequency determining part, like the exciter, receiver, or PA deck.   A table of all of the exciters and the receivers that I know of is below.
  3. There is no practical way to change an intermittent duty cycle radio to a continuous short of replacing the power supply and the PA deck.
  4. The MSR manual refers to the GS models as the "Fully Optionable" models. There is no practical way to convert a base to a repeater with full performance as the repeat duplex kit includes a different backplane, a different receiver, a different exciter and a different PA deck, plus some additional metal shield plates. Yes, the MSR2000 Base can be converted for duplex repeat operation, it's just that something designed and built to run full duplex from the factory is obviously better. It's much easier if you have the duplex (repeater) backplane, which is the one with the PL and R1-Audio Modules laying horizontal above the main module slots. And there were repeater, one-receiver and two-receiver backplanes. Only the factory repeaters were shipped with the duplex backplanes.
  5. The "A" power supply was basically a 120v AC supply minus the power transformer and bridge rectifier - just a robust DC filter and a 9.6 regulator. The "K" power supply was made in Canada and was extremely rare in the USA. I've only seen one of them.
  6. Changing squelch types involves changing out the squelch card (or adding one if you have a carrier squelch station). The TRN5073 (click for a photo) is one of the duplex PL boards, the TRN5074 is a simplex PL board and has only one reed (which is why it can either encode during transmit or decode during receive, but not both at the same time).   There is a TRN5075 board and while it has two sockets I do not know if it is simplex or duplex (click for a photo). The parts list calls for a KLN6209A reed as the decode reed and your choice of a KLN6210A or a TLN6824A as the encode reed.   The KLN6210 and TLN6824 are the same reed, the TLN6824 is the older design with a metal case and the KLN6210 is the newer cost-reduced model with a plastic case.   I've used a pair of 6209s and a pair of 6210s out in the field and not noticed any difference.   I've also used a K-1000 reed and not noticed a difference.
    The TRN5076 is the duplex DPL board, the TRN5077 is the simplex DPL board. Here's a photo of the DPL board. The vertical blue bar that is next to the large chip at the top is a TRN6005 code plug. There is an article on this web site on how to make your own code plugs.The lower code element socket (J100) in the photo is empty.
  7. A "0" is a very rare beast as the market for wideband radios is very limited. It was a special order for the broadcast industry as some stations still had VHF and UHF remote pickup channels at the time these stations were current products. If Moto offered a narrowband MSR this column would have a "2" option, but to my knowledge they never did.
  8. The base station (simplex) exciters and recivers were all built for four frequency operation, the difference in the station was the number of channel elements that were included and the complement of the cards in the control shelf.
  9. I've seen one "7" unit, and could not figure out what the difference was. If anybody has any information on it I'd appreciate it. It wouldn't have been the first typo on the factory model plate that I've seen.
  10. Does anybody have any information on the "A" or "D" configurations?
  11. The manual does not explain the "X", and I've seen two MSRs that had the "X" at the end of the model number and could not figure out what the difference was. Can anyone shed some light on the topic?

The Model Tables, Option Tables and Specifications from the 6881061E50-C VHF manual   1.7 MB PDF file
From these tables you can fully decode the cabinet model number and figure out what your station was originally shipped with. Note that the full manual PDF is available below.

Station Notes

VHF Low Band or Mid Band (30-50 MHz or 66-88 MHz)
As far as I know, there never was a MSR2000 on low band or mid band.
If a customer needed one Moto sold them a Micor station.


VHF High Band (132-174 MHz) Exciters
Model number
(plus A or B suffix)
(see note)		 Frequency
MHz		 Filtering
(see note)		 Mode Module
Connector		 Notes
TLD9231 132-150.8 No Simplex Female  
TLD9232 146-174 No Simplex Female TLD9232BPR top photo
TLD9232BPR bottom photo
both by Tim Ahrens W5FN
TLD9241 132-150.8 Yes Duplex Male  
TLD9242 146-174 Yes Duplex Male TLD9242B top photo
TLD9242B bottom photo both by WA6ILQ
The manuals that this information came are from my files, and are early versions.
I know that there are additional exciters that were developed after my manuals were printed.
If anyone has additional model numbers that should be in this list but are not just email me the information and I'll add them.


VHF High Band (132-174 MHz) Recievers
Model number
(plus A or B suffix)
(see note)		 Frequency
MHz		 I.F. Frequency
(see note)		 Filtering
(see note)		 Mode Module
Connector		 Notes
TRD6171 132-150.8 10.7 MHz No Simplex Female  
TRD6172 146-174 10.7 MHz No Simplex Female  
TRD6181 132-150.8 10.7 MHz Yes Duplex Female  
TRD6182 146-174 10.7 MHz Yes Duplex Female TRD6182A top photo
TRD6182A bottom photo
both by WA6ILQ
TRD6191 132-150.8 10.8 MHz Yes Duplex Female  
TRD6192 146-174 10.7 MHz Yes Duplex Female  
TRD6302 146-174 10.7 MHz Yes Duplex Female TRD6302APR top photo
TRD6302APR bottom photo
both by Tim Ahrens W5FN
The TRD7171 and 72 are normally used with single receiver non-duplex stations. The TRD6181 and 6182 are normally used with either two-receiver stations or on repeater (duplex) stations. The TRD6191 and 6192 are used whenever a shifted IF is required. All of these receivers can be configured for up to 4 frequencies, but no more than 2 MHz from lowest to highest frequency.
The manuals that this information came are from my files, and are early versions.
I know that there are additional recievers that were developed after my manuals were printed.
If anyone has additional model numbers that should be in this list but are not just email me the information and I'll add them.


UHF (406-512 MHz) Exciters
Model number
(plus A or B suffix)
(see note)		 Frequency
MHz		 Filtering
(see note)		 Mode Module
Connector		 Notes
TLE ? 406-420 ? Simplex ?                                       
TLE ? 406-420 ? Duplex ?  
VTE4001A 406-420 Yes Duplex Male VTE4001A top photo
VTE4001A bottom photo
both by VE2TSO
TLE5502 450-470 No Simplex Female  
TLE5512 450-470 Yes Duplex Male  
The VTE-series exciters were shipped only in the Canadian-built stations for use in Canada.
The manuals that this information came are from my files, and are early version USA manuals.
I know that there are additional exciters that were developed after my manuals were printed (like the TLE 406-420 MHz).
If anyone has additional model numbers that should be in this list but are not just email me the information and I'll add them.


UHF (406-512 MHz) Recievers
Model number
(plus A or B suffix)
(see note)		 Frequency
MHz		 I.F.
Frequency
(see note)		 Filtering
(see note)		 Mode Module
Connector		 Notes
TRE ? 406-420 10.7 MHz ? Simplex ?  
TRE ? 406-420 10.7 MHz ? Duplex ?  
VRE4001A 406-420 ? Yes Duplex Female VRE4001A top photo
VRE4001A bottom photo
both by VE2TSO
TRE6152 450-470 10.7 MHz No Duplex ?  
TRE6162 450-470 10.7 MHz Yes Duplex Female  
TRE6172 450-470 10.8 MHz Yes Duplex Female  
TRE6153 470-512 10.7 MHz No Simplex ?  
TRE6163 470-512 10.7 MHz Yes Duplex Female  
TRE6173 470-512 10.8 MHz Yes Duplex Female  
TRE6262 450-470 10.7 MHz Yes Duplex Female TRE6262A top photo
by WA6ILQ
TRE6263 470-512 10.7 MHz Yes Duplex Female  
TRE6272 450-470 10.8 MHz Yes Duplex Female  
TRE6273 470-512 10.8 MHz Yes Duplex Female  
The TRE6162 and 63 are the most common receivers. The TRE6172 is used where a shifted IF is required (i.e. 2-receiver stations). All of these receivers can be configured for up to 4 frequencies, but no more than 2 MHz from lowest to highest frequency.
A quick way to tell what split of reciver you have in your hand: If the UHF preselelector part number ends in "D56" you have a 450-470 MHz unit, if it ends in "D57" then you have a 470-512 unit.
The VRE-series receivers were shipped only in the Canadian-built stations for use in Canada.
The manuals that this information came are from my files, and are early version USA manuals.
I know that there are additional recievers that were developed after my manuals were printed (like the TRE-series 406-420 MHz ones).
If anyone has additional model numbers that should be in this list but are not just email me the information and I'll add them.

More notes:

  • There are at least three different vhf high band power amplifier models... the 110 watt inttermittent duty power amplifier works pretty well at about 60 watts continuous duty in a well vented and cooled radio vault, but you need to add fans, and if they die so does the power amplifier. The continuous duty rated amplifier deck will do continuous duty only if it is operating in the proper band segment for which it was built. And the range change / conversion parts are no longer available.
  • An easy to tell if you have the intermittent or the continuous duty amplifier: if yours has heatsink fins all the way across the rack panel, you have the continuous duty PA. If the fins only go about halfway across, it's the intermittent duty PA.

    This is the continuous duty power amplifier


    This is the intermittent duty power amplifier

  • If you have the intermittent duty amplifier, use two fans, and mount a Klixon snap-action thermostatic switch to the hot end of the heat sink, and wire it such that when activated it turns on the spare fan and also trips an alarm on your repeater controller (maybe the courtesy tone changes from a single dit to a Morse "H" (for Hot) and the MCW ID gets a "[space]OT" for OverTemp added to the end).   Or something. Look at the fan segment of the Mitrek Interfacing document for a diagram on how to use one Klixon for both functions.


    This is one way to fan cool an intermittent duty amp.

  • The early "A" versions of the PA (those that had a part number of the format like TLD2602A and ending with "A") would fail if you looked at it cross-eyed. The later version that had the part number ending with a "B" was much improved and could better deal with reactive loads and heat problems.   If you are going to buy an MSR, you really, really want to avoid the "A" version PA decks.
  • UHF PA's were built in three band segments.   There's the low split 406-430 MHz version, there's the 450-490 MHz range, and there's the high range 485-512 MHz range.   And there is no way of changing a 406-430 or a 485-512 to 450-490.
  • The MSR station has been known for developing intermittents in the blackplane if a connector pin is bent and then straightened (the force used to bend and then straighten the pin frequently cracks the solder). This is especially true on audio connections - the symptoms are that the audio level can wander, become distorted, etc.
    The fix is simple and permanent: Assume that any pin that has been bent (and then straightened) on any card slot will have to be resoldered. Use a good strong magnifying glass (or a set of binocular magnifiers) and check every bent pin on the card socket for cracks between the pin and the solder or between the solder and the trace. On any that are suspicious use a flat toothpick to dab a tiny bit of flux on the surface of the solder then reflow it using a long thin soldering tip. This is also true of the pins on the receiver, exciter and PL board.
  • Note that the MSR2000 station does not have a built in speaker - it's either in a small box that plugs into the backplane (TRN5079), or it's part of the test set (TRN5080).   You can connect a regular 8 ohm mobile speaker with no problems.   Just plug it onto the pins labeled "Speaker" (look at the cable coming in from the right). The speaker is on the R1 Audio card slot card slot pins 22 and 23 (look in the lower right corner).
  • The chassis metering jack(s) is(are) on the BACK of the card cage, and you have to tilt it down and forward so the metering plug is inserted from the back of the back plane.   Not through the PL board slot. The "official" MSR test set is a TRN5080A or B. You can download the manual for it here (it's just the three pages extracted from one of the manual files).
  • The multi-PL tone decoder module for the card cage is the TRN5329x (where x is blank, A or B indicating the hardware version).   When used in the stock repeat shelf, this card allows the repeater to respond to up to four additional tones on the receiver input, ORed on the card to the single status line that tells the control shelf that the PL tone has been decoded.   With the MSR configured as a full duplex base station, and cabled to a repeater controller, it can feed the repeater controller inputs and tell it which tone is being received.   One common use of multiple tone decode is on a club machine, with the first tone (for example, 100 Hz) listed in the local repeater directory, and the second (perhaps 146.2 Hz) used by club members.   You would program the repeater controller so that the 100 Hz tone would provide local repeat, and the 146.2 Hz would allow autopatch and other system toys.   Installing this card does not preclude any other options as it slides into the otherwise unused tone burst decoder slot.   Click here for a photo.   Click here for the manual, 2.03 MB.   The equivalent card for the Micor station is the TLN5745x Multi-PL Decoder (again, where x is blank, A or B indicating the hardware version).
  • If you need to make up a custom card for your system the Timeout Timer card (click here for a photo) is a good candidate to get stripped, then mount a piece of perfboard on it using some standoffs, and build your trick circuit on the perfboard.   I saw one where the gentleman made up his own multi-PL deoder card for the tone burst decoder slot by stripping a timeout timer card and mounting two Com-Spec TS-32s on it.
  • The local speaker volume control is a screwdriver adjust accessed through a hole in the control card metal endpiece.   One very common modification is to replace that potentiometer with one that has a real shaft and a regular knob, one good candidate is from Mouser, part number 774-270X232A253B2A1 (25K audio taper) or p/n 774-270X232A253B1A1 (25K linear taper) at under US$3. A matching knob is Mouser p/n 506-PKG40B1/8 that will run about US$1.55 (both the pot and the knob are 1/8 inch shaft parts).   The new pot can be mounted into a new hole the endplate then you run three jumper wires from the pot terminals to the circuit board where the original pot used to be.   See this article for a similar mod to a Micor Aux Receiver card.   Once you've mounted a new pot you can mount an LED into the old hole using a mounting clip and wire it to the COR line per the VE6SBS mod info below.   You'd think it was Moto stock.
  • A regular Mitrek / Micor / Syntor mobile microphone can be plugged into the front of the TRN5069 receiver control card (click here for a photo) to provide local keying and local microphone audio.   The station audio card has the microphone audio mix function built in.   Just mount a mobile mic clip to the chassis and you are done.   Since the standard mobile mic has a set of normally open switch contacts in series with the element you won't be picking up any in-cabinet noise if you leave the microphone plugged in.


    The above photo illustrates the last two points. And yes, in this photo the card is on an angle because the left hand card guide is missing.
    • So if you are looking for a used MSR the ideal station is a xnnKSB-31xxBT, CT or DT series (where "x" is the appropriate letter and "n" is the appropriate number), and a GSB series will do just fine at reduced power and a with a fan.   And if you end up with a GSB series you really want to mount a second (backup) fan controlled by a thermostat.

    By the way, after alignment of the receiver remove S201 (a rubber membrane type switch) on the receiver board. It has been known to short and cause dead receiver symptoms. This is especially important if you are placing the repeater in a remote location.   Personally, I replace it with a couple of pins that I can put a clip lead across when needed.   I've been known to use couple of cut-off-resistor leads left over from stuffing a PC board, soldering and then trimming the leads.

    And at some point open the harmonic filter on the PA and take a look around with a magnifying glass and take a good sniff as well... They have been known to burn internally, especially under out-of-tune conditions.

    Useful MSR2000 Manuals, etc.       Click here for instructions on how to order manuals

    Prices quoted below are Moto "NSO" Pricing ("National Service Organization") - the prices that Moto charges their service shops. Pricing to the public may be higher. Prices are changed quarterly, so use the mentioned prices only as indicators.


    Downloadable MSR2000 Manuals:

    The following sections from the MSR2000 VHF Service Manual (6881061E50) were scanned and submitted to Repeater-Builder. Click on each one to download it.
    Note that these files are just the RF sections, you still need the 6881061E40 Control and Audio manual.

    Does any one have the updated info that covers the "B" version power amplifiers ?

    The following sections from the MSR2000 UHF Service Manual (6881061E55) were scanned and submitted to Repeater-Builder anonymously. Click on each one to download it.

    Alingment information and notes:

    . The official MSR2000 test set is the TRN5080 (click here for a TRN5080 photo) or you could use a standard Moto test Set with the proper cable kit.
    Schematic and parts list   Photo courtesy of David Stanford K7IOU
    Anybody have a photo of the test speaker (a TRN5079) ?

    I'm going to put this in large type: You must use an analog meter for the RF alignment. Moto made a test set specifically for the MSR2000 stations and internally it is a 50µa meter. On the voltage scales it functions as a 20,000 ohms-per-volt voltmeter. There are two good reasons for this:
    1) ALL of the metering points on radios of that era were configured to use either a 50µa meter to ground, or a 20k-ohms-per-volt meter, and the measurement circuit uses the resistance of the test meter as part of a series circuit (from the test point to ground). Without a load of the correct value none of the metering readings were meaningful.
    2) There were no inexpensive portable DVMs when these radios were being designed - every two-way tech had either a Motorola test set or a homebrew replacement, or a portable VOM (a Simpson 260, a Triplett 630 or the WW2 surplus military equivalent) that had a 50µa scale.The voltmeter scales were based on that 50µa movement which produced a 20,000-ohms-per-volt voltmeter. Modern DVMs have a input impedance that ranges from 2 to 11 megohms (depending on the manufacturer and model, most are 11 meg) and without the proper 20k-ohms-per-volt load none of the book measurement values will be correct.

    In other words, YOU CANNOT USE A MODERN DVM TO PROPERLY TUNE AN MSR2000.

    Two additional "gotchas" are that most inexpensive DVMs go crazy in the presence of RF energy due to the fact that they are sold by price, so to maximize the profit the manufacturers scrimp on the shielding, and lastly, in every case you are tuning for a peak or a dip - attempting to do that with dancing numbers on a DVM is an exercise in frustration - you are constantly trying to determine if the new number is higher or lower than the last number and your brain can't keep up with the DVM display update rate. You are tuning for a peak or a dip, you NEED an analog needle meter to see the peak or dip.

    Another key to aligning / realigning the MSR2000 Receiver and Exciter strips is to follow the first pre-alignment task item listed in the service manual: back all the inductor (coil) cores out of their forms to the locations indicated in the slug position graph.   One useful trick is to put a flap of tape on the tuning tool - not only does it help in counting turns but it also helps prevent the tool from rolling off the workbench.

    Then start your new alignment from scratch. At least one of the meter dip / peak indications is very, very small and easy to miss. If you mistune that stage nothing after it works right so pay very special attention to the actual meter needle movement as you go through the steps.

    One of the handiest things to have around when you are troubleshooting a radio is a logbook that lists the meter readings from when it was working properly. I really suggest that you have a station logbook that starts the day you receive the station, and notes what the frequencies it was on when it was received, and a FULL set of meter readings of the receiver, exciter and PA deck on the old frequencies. Then duplicate that info on the new frequencies. If you later on have problems, you can figure out what stage has taken a hit by comparing the readings.

    .Alignment of the MSR2000 station VHF receiver   180kb PDF document

    .Alignment of the MSR2000 station VHF transmitter   4.6MB PDF file
    This covers both intermittent and continuous duty models

    .Alignment of the MSR2000 station UHF receiver   176kb PDF document

    .Alignment of the MSR2000 station UHF transmitter   1.2mb PDF document

    Articles:

    .Conversion of an MSR2000 station to an amateur repeater        By Henry Wingate K4HAL

    .A status display for the MSR2000 station         By Henry Wingate K4HAL 

    .Another conversion of an MSR2000 station to an amateur repeater       By David Stanford K7IOU   (offsite link)

    .Conversion of an MSR2000 station for the WØDOD repeater   By Nate Bargmann, NØNB

    .There is one interfacing technique that we don't have an article on... it was described to me over dinner a few years ago...
    Take a card like a timeout timer card, strip it, mount an RLC-MOT (and optionally a PL tone decoder) on standoffs, then mount a DB15 into the front sheet metal. Slide that interface card into the squelch gate slot. Use the DB15 to connect the repeat audio, COR and PL decode signals to an external controller. The same card can inject repeat audio from the controller into the backplane.
    The controller interface card hadles the repeater in normal use, then if the outside controller takes a dive you can unplug this interface board and plug a regular (unmodified) squelch gate card in to get the system back on the air. Using a squelch gate card does not provide an identifier, but does give you a good emergency kerchunk box (a very basic repeater). The different sounding squelch tail and different carrier delay timer duration will tell your users that the backup "control" system is in place and that they need to voice ID the system.

    .Modifications to the MSR2000 cards by VE6SBS for the VE6NHB repeater     Original article, offsite link
    I suggest you read the entire article first.

    Here are the schematics of his modified MSR2000 card cage and cards: (all are pdf files)
    The modifications on the schematics are not visible - the modified prints look just like original Moto schematics - you will have to compare them to the originals to determine the changes.
          .Backplane wiring   5.1mb
          .TLD9232 exciter   555kb
          .TRD6182 receiver   618kb
          .TRN5069A R1 Audio Squelch   442kb
          .TRN5075A PL encoder decoder   423kb
          .TRN5321A Station Control   343kb
          .TRN5331B Squelch Gate   509kb

    . Documentation on the TLN6721CDX TX Alarm card - provided by A. Nony Mous (click on the link for photos of the card)
    This card was designed for the Canadian Provincial Police system of over 600 MSRs that was decomissioned about 2002. These were a mix of continuous and intermittent duty 136-150 MHz stations that were deployed in shelters that had battery backup and local AC generators, and an adjacent radio tower, with all of the sites linked by microwave shots. The relay contacts on this card were integrated into the site alarm system. There is a downloadable 4-page PDF containing a theory writeup and schematic linked to this page.

    . Documentation on the QLN2812A Station Identifier Field Modification Kit - provided by John Gilbert KA4JMC
    This kit was made up of a QRN8424B or QRN8425B module, the QKN7547A cable, this documentation and a few other loose pieces.
    The QRN8424B is used in Micor stations, the QRN8425B module is used in MSR2000 stations.
    This module uses a fairly inflexible design - the IDer audio frequency (1,200 Hz) is slaved to the IDer morse code speed. The IDer spacing is either 15 or 30 minutes (but is dependent on the timing of a 555 chip). Both of these modules use a 256x4 PROM chip that is almost pure unobtanium (Monolithic Memories MM5301-1). Each byte represents one time frame, a dit requires two frames, a dah requires four, a word space requires five. Module overhead uses 31 frames. The rest can be used for the actual IDer string (the Morse code sequence). An adapter could be made to allow use of a 27nn or 27nnn series chip, but it's much easier to use an external repeater controller like an NHRC, Scom, etc., but since FCC Rules require you to be able to remotely switch the repeater on and off you need a real repeater controller anyway... and you can buy a decent one for under US$160 (the NHRC-4)

    . Documentation on the TLN640CDX IDer card - provided by www.radiowrench.com       Photo of the card
    No, that's not a typographical error, that part number really has only three digits rather than four.
    If you have an MSR that uses this IDer it's MUCH easier and more flexible to ignore / remove this card and use an external repeater controller like an NHRC, Scom, etc. as this card uses an almost-impossible-to-get 32x8 one-time-burnable PROM chip (yes, 256 bits), plus almost nobody can burn them any more. Yes, you could build a socket adapter and plug in a more modern 27nn or 27nnn series PROM chip, but since FCC Rules require you to be able to remotely switch the repeater on and off you need a real repeater controller anyway... and you can buy a decent one for under US$160 (the NHRC-4)
           Cover page (info on the donor)     Pg1 440kb     Pg2 51.4kb     Pg3 43.4kb     Pg4 93.8kb     Pg5 33kb
           Pg6 55kb (programming chart)     Pg7 40.5kb (parts list)     Pg8 1.32mb (schematic right half)     Pg9 1.25mb (schematic left half)
           Pg10 1.35mb (PCB layout pg1)     Pg11 1.4mb (PCB layout pg2)        All of the pdfs in one zip file for easy downloading

    . A real repeater controller is much more flexible, but if you absolutely have to put a card-based IDer into an MSR shelf you basically have three options:
    1) Mount a mini-repeater-controller like an NHRC-4 or a ICS Basic on a stripped Time Out Timer card and plug it into the Squelch Gate card position, or
    2) Go read the "An IDer for the MICOR Repeater Shelf" article by Jerry Matthews WAĜUZI located on the Micor page at this web site then build it on a stripped down line driver card as shown, or
    3) Purchase an ID-O-Matic kit (for about US$20) from NĜXAS (at http://www.hamgadgets.com), build it, mount it on a stripped-down Time Out Timer card, and patch it into the transmitter audio in the shelf as shown in the Micor IDer article. Like the ID-8 that WAĜUZI used all you need to do to make the ID-O-Matic module work is to hook up power, ground, COR, PTT and audio out, then program it. You may need the buffer amplifier that WAĜUZI used.

    . Documentation of the various jumpers throughout the station - provided by George Henry KA3HSW
    Includes the backplane and the various plug-in boards. Compiled from several MSR2000 manuals.



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    This page was created August 1, 2009 by splitting the MSR2000 information off of the Mitrek index page.

    Thanks to Tim Ahrens W5FN for his photos.
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