Tram Titan II no recieve

[43]

Working on a Tram Titan II it has good sound from the speaker. But no audio, just white noise (like its receiving on a different Freq). I checked all the tubes with my tube tester, all good there. Recent work on the caps(seems like they were all replaced recently). Keying up another radio no signal at all. The reciever gets Loud with the volume and Rf control. but just noise, ALSO the transmitt is showing about 2 watts output but no reading on the Freq counter. What is Common to both the transmitt and the recieve?

[Night Ranger]

Jan 11, 2013 15:26:32 GMT -5 43 said:

What is Common to both the transmitt and the recieve?

Probably a crystal oscillator used for one of the IF frequencies.

Checking CBC crystal mixing charts....

Yep. See the crystal mixing chart below for the Tram Titan IIa, 27D and 27 E.

www.cbcintl.com/XTALS/Tram%20Titan%20IIA,%2027D,%2027E%20Xtals.pdf

Night Ranger

[Sandbagger]

Jan 11, 2013 15:26:32 GMT -5 43 said:

Working on a Tram Titan II it has good sound from the speaker. But no audio, just white noise (like its receiving on a different Freq). I checked all the tubes with my tube tester, all good there. Recent work on the caps(seems like they were all replaced recently). Keying up another radio no signal at all. The reciever gets Loud with the volume and Rf control. but just noise, ALSO the transmitt is showing about 2 watts output but no reading on the Freq counter. What is Common to both the transmitt and the recieve?

There really isn't much common between the transmitter and the receiver in a Titan other than the power supply and the audio section. There is no synthesizer for frequencies. The transmitter uses a single crystal per channel, and the receiver is a simple tunable design, with a fixed 31.5 Mhz 1st L.O. crystal. It's possible that the tunable receiver oscillator is off-frequency, making the dial line up incorrectly. So you might want to try tuning the receiver dial while you transmit on the other radio to see if you can find the signal somewhere else. Receiver hiss is usually a good sign. It means that at least some of the RF stages are working. If you can't find the signal by tuning around the dial, it's possible that there's a problem with either the 1st or 2nd L.O. Someone might have modified the radio to drop below channel one, and it may not be set up to receive the normal channels.

As for your transmit, you may have a bum crystal or two. Try checking all the channels to see if any of them work. If the radio was modified to receive out of band, it's also possible that the transmit section was modified for use with an external VFO. Look to see if there are any unmarked jacks on the back panel of the radio. If it's putting out any power at all, there has to be SOME level of frequency reading. If it's unstable, it probably means that the transmitter is self oscillating, instead of using the crystals.

[Sandbagger]

Jan 11, 2013 16:20:58 GMT -5 Night Ranger said:

Jan 11, 2013 15:26:32 GMT -5 43 said:

What is Common to both the transmitt and the recieve?

Probably a crystal oscillator used for one of the IF frequencies.

Checking CBC crystal mixing charts....

Yep. See the crystal mixing chart below for the Tram Titan IIa, 27D and 27 E.

www.cbcintl.com/XTALS/Tram%20Titan%20IIA,%2027D,%2027E%20Xtals.pdf

Night Ranger

That chart is misleading. It shows a column for crystals used for both TX and RX, which is not true on the Trams. He is correct in the written explanation of how it works though. But there is no crystal receive. Only the tuner..

[FIXR]

There is a 22K 2W carbon resistor that sometimes opens and shuts off the receive. It is located on pin one of the 6BK7 tube that is in front of the mechanical filter.

Alan

[43]

Thanks for the replies!!!!

Fixer YOUR THE MAN !!!!
Checked that resister and it was opened
Changed it out and Voila got receive.
Don't know how I missed that second thing I did after checking the tubes was to check for open resisters.Anyway on to checking out the rest of the rig
Again Thanks for the help guys!