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HELP! Tram needs some work!

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Jester

HELP! Tram needs some work!

#145065

Post by Jester »

Ok, so my Tram D201A needs some work, I just don't know what the problem is! Here is a breakdown of the issues:

Some channels don't receive. For instance, 37 doesn't come in unless I switch to 36 or 38 and come back real fast...

SSB seems to be off frequency.

Recv could be better in some cases, as some people sound off freq...

I want to get this radio back to its former glory, any ideas of what might be wrong and what I can have done to have it back to tip top shape? Maybe having it re-capped or new tubes? Looks like I have a major project on my hands....
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TwentyTwo-Zero
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#145071

Post by TwentyTwo-Zero »

Just taking a quick glance at the owner/service manual for that radio it may be weak tubes or a faulty crystal. I know I'm "plugging" the site a lot today, but the manual is available at cbtricks - it contains a troubleshoot section that (again at a quick glance) describes similar symptoms to what you are having. I'd d/l the manual, then test the suspect tubes. You might get off "lucky" by only having to replace a tube or two. I think it also tells how to test the crystals, but if you don't have the equipment this (and alignment procedure) may need to be done by a shop. Best of luck, and I hope it turns out to be something simple...
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And Don't You Eat That Yellow Snow...Frank Zappa
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CPI • Cobra • Icom • Yaesu
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silverstreak
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#145096

Post by silverstreak »

Those old radios first thing to do is recap and retube then do a alignment and go from there.
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drdx
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#145097

Post by drdx »

Welcome to the world of old radios. Those things were kinda high maintenance when I ran one 20 years ago, and they weren't very old back then. Stock up on those old 12BY7A's too. -drdx
Yes it's me, Dollar-98, drdx, the original all maul, shot cawla on workin this no-fade technology.

-drdx
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Popcorn501

#145112

Post by Popcorn501 »

Send it to Gregg Barkett At Barkett Electronics in Al he is the master on those.
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lonesome 500
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#145115

Post by lonesome 500 »

Popcorn501 wrote:Send it to Gregg Barkett At Barkett Electronics in Al he is the master on those.
he is tha man.....on those and brownings.......no doubt
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Jester

#145121

Post by Jester »

I found some 12BY7A's at a website online, surplus something or other....are these good tubes to use? I heard tubes out of a high-end guitar or bass amp are better...is this true?

I will stock up on these if recommended....BTW, which is the best tube to get, anyone have any suggestions? Also, I have a tube enthusiast/ham op near me who is very informed about these radios and I can go to him for help...
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preacherman
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#145135

Post by preacherman »

Welcome to the world of old tube radios. :D
It sounds like the recieve problem is in two areas:
One...the channel selector switch on those radios is notorious
for getting dirty or going out. When it starts to do that, the first
symptom is sudden loss of recieve (from time to time) on certain channels.
solution: First try contact cleaner. Second, have someone repair the switch.
Third, pay big bucks for a new switch.

The second area is in the crystals for the channels. On those radios, they
are very close to the modulator tube and get a lot of heat. They fail and
at times the tuning caps for each crystal fail due to heat and drying out.
If your transmit is of freq...you can tune each crystal back to freq providing
the age and heat don't make the variable caps fall apart :roll:

Great radios, but high maintenance.
preacherman
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Night Crawler
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#145142

Post by Night Crawler »

preacherman wrote:Welcome to the world of old tube radios. :D
It sounds like the recieve problem is in two areas:
One...the channel selector switch on those radios is notorious
for getting dirty or going out. When it starts to do that, the first
symptom is sudden loss of recieve (from time to time) on certain channels.
solution: First try contact cleaner. Second, have someone repair the switch.
Third, pay big bucks for a new switch.

The second area is in the crystals for the channels. On those radios, they
are very close to the modulator tube and get a lot of heat. They fail and
at times the tuning caps for each crystal fail due to heat and drying out.
If your transmit is of freq...you can tune each crystal back to freq providing
the age and heat don't make the variable caps fall apart :roll:

Great radios, but high maintenance.
preacherman
You beat me to it. :wink:
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Jester

#145440

Post by Jester »

Any tips on tuning crystals? I'm thinking the heat generated may have caused them to drift over time....after all, the radio is about 33 years old or so..

I'm thinking of scooping up a few 12BY7A's, and whatever else I can scrounge for stockpiling....
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#145766

Post by Night Crawler »

Jester wrote:Any tips on tuning crystals? I'm thinking the heat generated may have caused them to drift over time....after all, the radio is about 33 years old or so..
Try putting a trimmer cap in parallel or in series with the xtal around 10 pf
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