Realistic TRC-55

[Kilroy08]

I finally dug out a TRC-55 that was given to me as a gift.

The darn thing is off frequency by 2 megahertz and some change. Will doing an alignment fix this, or should I look at some new crystals?

[Night Crawler]

What band is it on ten meters?
If it's off by 2mhz your going to need an alignment and a change of crystals.

[TheCBDoctor]

Hi Kilroy08

Is it off on all channels by the same amount? A modern radio will be off frequency by the same amount. An older radio with a crystal matrix may only be off frequency on a select number of channels. Try all the channels, if it does use a crystal matrix, and it is off on all the channels by the same amount, then it would not be the crystals in the matrix. It may be in the mixer section of the radio. Try pressing on the board when you key up.

That is the first thing I do with any radio. Sometimes the radio will act up and pressing on the board will show if you have a cold solder connection. That is the first test I would try.

Good luck,

[Kilroy08]

It's up in the top of the ten meter band, and all the channels are off by 2 MHz or so.

I gave up on it for the night. I was just happy that my repair job on the AC power socket worked. Had to notch out the back of the cabinet to install a connector from a dead PC power supply to replace the non existent factory one.

I'll probably get back into it sometime this weekend.

[Night Crawler]

Check the bank of 37mhz crystals and see if they're changed. That was a common way of moving those old radios with that type of crystal mixing circuit up to 10 meters. Sounds like someone put that radio up on 29mhz in the AM part of the 10 meter band.

What you would have to do to get it back on 11 meters is put back the bank of 37mhz crystals and do a realignment.

[Kilroy08]

Thanks, that's what I was thinking. I'll pull the cover off later and check on the crystals later today.

[Foxhunter]

That could be interesting to keep as a 10M radio as found. I think it'd be kind of neat to keep. I've never modified one like that (myself) but from reading before somewhere on a Ham website, it seems like some people have spent some time and gone through some trouble to convert them, the degree of difficulty depending on the model. It'd almost be a waste to switch it back.

I have a Tram Diamond 60 (D60) that was nicely converted for parts of 10M, and decided to certainly keep it that way. I also have a Tram Diamond 60 that's as originally designed for 11M. It's nice to have two versions of the same neat radio. Think about keeping it and getting a 2nd stock unit. Just throwing that out there for consideration.


Foxhunter 351 NJ

[Night Crawler]

Thanks, that's what I was thinking. I'll pull the cover off later and check on the crystals later today.

Correction the crystals in the stock TRC-55 are 33mhz not 37mhz.

Here's the crystal mixing chart.
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[Night Crawler]

That could be interesting to keep as a 10M radio as found. I think it'd be kind of neat to keep. I've never modified one like that (myself) but from reading before somewhere on a Ham website, it seems like some people have spent some time and gone through some trouble to convert them, the degree of difficulty depending on the model. It'd almost be a waste to switch it back.

That's what I would do leave it on 10 meters I'm sure when the band opens up there will be some AM activity.
To replace the bank of crystals it would cost more then if you were to buy a new radio.

I modified a Uniden Grant for 10 meters years ago but all that had to be done was to replace one xtal and do an alignment not much work. I also build a Discriminator Limiter Board and modulated the VCO to add FM to it but that's only thing that took some time and work.

[Kilroy08]

Ughh.... Darn computer I was using kept logging me out as soon as I logged in earlier today.

Pulled the crystals, case closed. It was converted to 10 meters. They should have run from 33.000 to 33.250 for the 6 primary crystals. Instead they were all in the 35 MHz range
In the immortal words of Bill Engvall, "Here's your sign."

The TRC-55 was going to be slated for the resurrection of the base station at the machine shop. Oh well, found a TRC-56 CB phone in the pile of random stuff......
Hmm.... footwarmer...... We might be able to pull off something on par with the old setup. Had a D&A Maverick and a Moonnraker 4 or 6 over there ,long before my time, can't remember what radio they told me they had though.

On the subject of a CB phone, pick up the handset........ Clear the Bowl! I'm making a long distance call!! lol

Thanks for all the words of wisdom.

[De_Wildfire]

If he can his radio to go off 2mhz off, can I convert one of those radio's over to 4mhz? I need something very small for the car that I can pick up at a flea market without putting any money out for all band radio. I'm only using it for emergency communications.

[Night Crawler]

What frequency do you want to put it on?

[De_Wildfire]

What frequency do you want to put it on?

4200.0

[Night Crawler]

Can't be done not by changing a few xtals and doing an alignment.
It's one thing to modify an 11mtr radio to 10mtrs which is very close in frequency but to get it down to 75mtrs you would have to rebuild the radio or homebrew a transverter.