RE-TUBING A TRAMD201A

[dirtyjob]

I own a Tram d201A and want to have it completely re-tubed, the radio runs ok right now but i know the tubes are very old that are in it now, my question is this:

Can i simply replace the old tubes with new ones and thats that or as i have heard, after a re tube the radio needs to be aligned?

any knowledgeable responses greatly appreciated.

[51]

for the most part just retube it and your good to go. if anything though i would check and adjust if necessary the bias with the new tubes installed as well as check the grid resistors to make sure their still up to specs.

[379 stringbean]

Keep in mind too that just because their new old stock tubes dont always mean they test as new.Ive bought NOS tubes that were shorted or less than the origionals that say tram.I've also had origional tram tubes that still tested very high.If you dont have a good and I mean good (calibrated)tube checker to test your tubes,then its a crap shoot.The 6gh8a seem to be the the most finicky.A lot of people only do one test for them and they have 2.One side will test excellent and the other will be weak.

[dirtyjob]

good info, i thank you both

[dirtyjob]

my tram worked great when stored away, no that i brought it back to service it transmits and has decent output/audio however the receive seems to be lacking, anyone know which tube i should test for such an issue??

[379 stringbean]

Heres a link to cb tricks data base for the manual.The page your looking for is 32 and it will give you different options as to your symptoms.Page 31 will give you the tube #'s in relation to the chart # (v301)the symptoms page gives you.If I were you I'd print out the whole manual.Or buy one on ebay.I only have 23 ch 201's.

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[51]

for the receiver portion you will want to test the 6BQ7A, 6BK7B, 6BA6, 6GH8A tubes. go to CB TRICKS.COM and download the schematic, its your road map to success.
they also have the owner/service manual as well. watch those high voltages!

[dirtyjob]

im there, thanks.
will do with the high voltage, i got belted years ago with a cap from a browning.....

[51]

yea it sux. anyway good luck on that rig.

[dirtyjob]

thanks again your help was great, i have a eico tester for the tubes, im ordering a whole set for the d201a for a re-tube, lets get this beast back in action "hopefully"

[crazy_cooter]

Hey I wanted to throw in a suggestion for your Tram if you don't mind....if you have the model which has the printed circuit boards, have it checked over. Mine had several cold solder joints as well as melted solder joints and burned traces in the board. I guess it's pretty common in the 201 a's and usually is the weak point in these radios. Just some friendly advice to pass along, good luck!

[crazy_cooter]

I forgot to mention too that the crystal selector dial had some issues as well. Once they get wore out, the radio will sometimes not transmit, or you would have to fiddle around with the selector knob to get it to transmit again. As far as i know, a new crystal selector is no longer available for the radio anywhere. And chance of finding a good used one is slim to none.