Batboard

I've never worked on a MSF and don't have a manual (See my WTB post in the "wanted" forum" if you have one for sale). I suspect I may have a CLB variant in a CXB cabinet. This thing's a wreck.

How can I be certain of which variant I have? The shelf I have does not have the digital display, and on the system board there are two chips 1 labeled "code plug" and one labeled "program".

Thanks for any help or pointers.

My two bits worth:
You have the "analog" or the earlier version of the MSF.
The station is programmed with the Motorola R1800 programmer.
The Power supply, Power amplifier, as well as the internal modules of the RF casting are identical, there is a slight difference in the interconnect board.
Since this station does not appear to be all original, I would suggest compairing all of the module part numbers aganst the manual to be sure you don't have some 406-420 (UHF R-l) modules.
I have seen this, and they won't tune in R-ll.

The reason for the "digital" station is the ability to support Motorola voice encryption (DVP, DES etc) modules.

I highly suggest replacing the electrolytics on the control board next to the 5V power supply.

There ia also known problems with the injection filter (RX meter 3)

Test the station with the existing code plug before attempting to retune to another channel.

I can make a code plug for you.

To successfully tune this station you will need the RF probe from the tune up kit, Service monitor, MSF test set as well as the manual.

Thanks, Bernie.

Based on your comments, this is clearly not all original. The plate on the side of the cabinet indicates a 'cxb' model. I have the RSS/RIB/Cable, but no suitcase. I haven't had one in years. I may need your help, but, I'm not sure how far I want to go with this model of MSF. Given the side plate, I was hoping for a better result. The MSF is the only model I haven't spent a lot of time with.

I'll have to see if I can find some manuals - but, if there's no chance this is an RSS programmed model, I'll probably not spend too much time and money. I'm uncomfortable with something I can't change if I need to, and, I don't think an '1800 is going to fall out of the sky!

Rob

Ok, some progess, even without a manual. Is it safe to say that if the controller does NOT have a digital display it must be a CLB? Are there any CXB's without one?

Rob

My two bits worth:

NO.

Bernie,

"No" to which question?

I may have to take advantage of your offer to create a program for this beast.

Rob

My two bits worth:
"Any CXB with out a display?" NO.

There is no model of the "Digital" control board that does not have the 3 digit display.

I thought that I explained this in my first post.

The "Analog" station was the first version, which came out about 1985.
The "secure" Micor station remained in production until the "Digital capable" MSF came out about 1990, as did the VHF version.

Digital in the case of the MSF means that provisions are made for a secure board.
There are several variants of both boards due to manufacturing revisions.

There are also some minor differences in the audio circuits due to the band of operation.

It is possible to directly install an "analog" board in a "digital" station, however TTRC will not operate with the analog board.

A "digital" board may be installed in an analog station, so long as a jumper is installed to provide 5 volts for the receiver VCO.

As mentioned earlier it would be a good idea to check your module part numbers against the manual.

If you dont have the manuals I could look up the part numbers for you.

"...don't have a manual (See my WTB post in the 'wanted' forum ..."
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The manuals show up on ebay regularly. Here is one:

http://cgi.ebay.com/ws/eBayISAPI.dll?Vi ... 3834216074

You will also want the big CXB manual: 6881082E10 and the CLB manual: 6881062E75, both of which are NLA from Motorola.

My two bits worth:
I forgot to mention a few things to be aware of if you decide to take the station apart.

Be very careful of the pins on the feed thru connectors in the RF casting.
The pins can be bent when installing the UNI board.

If you remove the front end casting, or the interconnect board, allways remove the involved feed thru connectors. This will make re installation much easier, as well as reduce the likely hood of bent pins.

NEVER power up the station with the 9.6V regulator disconnected.
This is the cable going to the IPA module, as well as the ribbon connector on the control board. The reason for this is that the 5 Volt supply uses the 9.6V supply as a reference, and the 5V switcher can be damaged.