Ok, Here is the Skinny; I have a Micor High Power Base Station that i would like to Convert to Repeater Operation. What is Involved in Converting this into a Repeater?? The Model # is C73MHB-3140BR It has 2 Receivers and a 2 Channel Transmitter. I'm Pretty Stupid when it comes to this Model of Radio as it was WAY Before My time so any help would greatly be appreciated. I Would like to Convert this to Work in the 2-Meter 146Mhz. Range.
Mikey
Converting Micor Base to Repeater Operation
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George
- Posts: 266
- Joined: Wed Apr 16, 2003 11:14 am
- What radios do you own?: X9000, HT1550XLS, MTS2000, etc
Re: Converting Micor Base to Repeater Operation
Why would you want to convert this thing?
It's a Motrac and has tubes in it and you are FAR better served to go find a Micor and work with it.
Here's the problem...
First, you need a manual.
Second, this is an intermittent duty station. I am not going to pull a manual, but you want to ensure you have a control shelf in it.
Third, you need channel elements. Recrystalling has gotten just outrageous so plan on $75.00 each unless you want to change the crystal itself and chase the frequency around after ruining the temperature compensation. (Don't start with me on "I have been successful replacing crystals and haven't had problems" Maybe you have, but for every one you are successful with, I have taken one out of service and either set it to International or to my local dumpster. It's a load of crap and if you want it done right, send them to International.)
Fourth, you need a manual. Consult said manual and you will find all of the parts changes required. You will see how the coils in the front end change and what cap values change in the multiplier strings, both in the transmitter and in the receiver. Find each major kit number and do the breakdown to see what band range you have.
Fifth, you need manual. Consult said manual and you will see what parts you need to change in the power amplifier section and you will determine how many turns of what wire was used to go from range three to range two, etc. You will figure it out.
Sixth, you need a test set and proper Motrac adapter cables. Without this and a Manual, I did mention you needed a manual, didn't I, and a proper set of channel elements, you can tune up this station...but only if you have a service monitor.
Seventh, Once you find out if you tubes are any good and chances are that they are NOT, when looking up the parts required, making a nice spreadsheet so you can track your changes and seeing what all you need and finding out almost all of it is no longer available and finding out how much tubes cost, you will quickly come to the conclusion this station was not worth fracking with in the first place because it's an intermittent duty station and you would be far better served to go find yourself a nice Micor or MastrII and call it a day.
Eighth, If I didn't scare you off by now, you still need a timeout timer (most bases didn't have them) and you need a squelch gate card. Put those in, consult your manual for proper jumper settings and Vola! You have a repeater.
Nineth, Don't even begin to ask how to pervert this station to work with an external controller.
Scared? You should be. Go find a nice Mastr II.
Oh, and one more thing...this type of station probably has a control shelf in it. Those old style control shelves had chisel tip contacts on the cards that have a nasty tendency to tear away at the plating on the pins on the backplane. If you REALLY insist on using this thing, repin the backplane on the cards you intend to use and replace all of the contacts on the cards with the new kind. It will save you HOURS of trying to find that stupid intermittent condition that only occurs after the station has run for a month, then refuses to repeat, or unsquelch or something and you go out to the site, pull and reseat a card and the problem goes away.
The real question you need to ask yourself is, how much do you like pain? The question isn't if you like pain because we are talking Motrac here so we already determined that part.
zzzzzzzzzzzzzzzzzzzzz.................cpap engaged...................george.....wake me when I need to drive home...... nevermind............I am already here..................zzzzzzzzzzzzzzzz
It's a Motrac and has tubes in it and you are FAR better served to go find a Micor and work with it.
Here's the problem...
First, you need a manual.
Second, this is an intermittent duty station. I am not going to pull a manual, but you want to ensure you have a control shelf in it.
Third, you need channel elements. Recrystalling has gotten just outrageous so plan on $75.00 each unless you want to change the crystal itself and chase the frequency around after ruining the temperature compensation. (Don't start with me on "I have been successful replacing crystals and haven't had problems" Maybe you have, but for every one you are successful with, I have taken one out of service and either set it to International or to my local dumpster. It's a load of crap and if you want it done right, send them to International.)
Fourth, you need a manual. Consult said manual and you will find all of the parts changes required. You will see how the coils in the front end change and what cap values change in the multiplier strings, both in the transmitter and in the receiver. Find each major kit number and do the breakdown to see what band range you have.
Fifth, you need manual. Consult said manual and you will see what parts you need to change in the power amplifier section and you will determine how many turns of what wire was used to go from range three to range two, etc. You will figure it out.
Sixth, you need a test set and proper Motrac adapter cables. Without this and a Manual, I did mention you needed a manual, didn't I, and a proper set of channel elements, you can tune up this station...but only if you have a service monitor.
Seventh, Once you find out if you tubes are any good and chances are that they are NOT, when looking up the parts required, making a nice spreadsheet so you can track your changes and seeing what all you need and finding out almost all of it is no longer available and finding out how much tubes cost, you will quickly come to the conclusion this station was not worth fracking with in the first place because it's an intermittent duty station and you would be far better served to go find yourself a nice Micor or MastrII and call it a day.
Eighth, If I didn't scare you off by now, you still need a timeout timer (most bases didn't have them) and you need a squelch gate card. Put those in, consult your manual for proper jumper settings and Vola! You have a repeater.
Nineth, Don't even begin to ask how to pervert this station to work with an external controller.
Scared? You should be. Go find a nice Mastr II.
Oh, and one more thing...this type of station probably has a control shelf in it. Those old style control shelves had chisel tip contacts on the cards that have a nasty tendency to tear away at the plating on the pins on the backplane. If you REALLY insist on using this thing, repin the backplane on the cards you intend to use and replace all of the contacts on the cards with the new kind. It will save you HOURS of trying to find that stupid intermittent condition that only occurs after the station has run for a month, then refuses to repeat, or unsquelch or something and you go out to the site, pull and reseat a card and the problem goes away.
The real question you need to ask yourself is, how much do you like pain? The question isn't if you like pain because we are talking Motrac here so we already determined that part.
zzzzzzzzzzzzzzzzzzzzz.................cpap engaged...................george.....wake me when I need to drive home...... nevermind............I am already here..................zzzzzzzzzzzzzzzz
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Mikey
- Posts: 410
- Joined: Wed Sep 05, 2001 4:00 pm
- What radios do you own?: CDM1550 LS+, HT1250, MCS2000
Re: Converting Micor Base to Repeater Operation
Sounds Like Good Dumpster Material. I always wondered why i stayed with the MTR2000 as my repeater of Choice. Thanks for the Enlightment.
Mike
Mike