• You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.

Tram D201 meter spike in ssb transmit

klj2497

Active Member
Jan 19, 2017
222
47
38
60
When i key on ssb the meter will spike and then flutter before the meter settles on zero. it appears to transmit fine after the spike and flutter. With the watt meter hooked up the output also spikes beyond 12 watts and then returns to zero when i key up. I have swapped out the v401 and v602. and v600, v601, and v502 i also turned down the mic gain and keyed the mic, but still the same. Im stumped.
 
Last edited:

It noticed that on am it will also spike when i key. then it shows the right readings. I monitored the signal spike i could not hear any squeal or noise when it spikes I tried another microphone but no change. how can i check to see if the receive is disconnecting before the transmit connects?
 
Last edited:
klj2497,
I would do a very close visual inspection of the contacts. If I am not mistaken, the RX should disconnect a few milliseconds before the TX engages.
This phenomena exactly like the Browning Golden Eagles that used an electrolytic capacitor (many were changed to a higher value to prolong disconnection of the RX contacts) to delay disconnecting the RX for the "Squeal/Scream etc".
Could be your Tram has a "bent out of shape" set of contacts in the relay that is not allowing the delay in switching??

See the link below concerning Turner microphones. At the bottom of page 8 it describes a squeal in the first portion of TX and RX. It is stating that the audio circuit must be "made" at the same time the TX is "made". Slight bending of the contacts in the microphone is the recommended cure. I would think this scenario would apply to any other microphone as well.

http://www.cbtricks.com/mic_manuals/turner/turner_mic_wiring_book.pdf

If there is a delay in "making" the contacts for the audio line, I could see this causing your "spike" of the meter in SSB. You wouldn't necessarily hear it and doubtful anyone else would hear it on the receiving end in SSB-but maybe in AM??

Good Luck

73
David
 
Most likely needs a relay. It's a rare one, and expensive where you actually can find it. This creates an incentive to attempt "fixing" the relay.

Never makes it better, in my experience. Once the relay's spring fingers get bent from being "adjusted" the timing will never be right.

Barkett has it listed, near the end of this page: http://stores.goldeneagleradios.com/tram-base-radio-parts/?sort=featured&page=3

One other possibility. If the neutralizing capacitor C706 has been tweaked to max the wattmeter reading, the final will become unstable.

C706 is properly adjusted to prevent the final tube from oscillating, especially in sideband with no modulation. Can create quirky symptoms in AM mode.

When it's adjusted properly, there will always be some friction on the adjustment screw. If it's been cranked so far counterclockwise that there is no friction on it, this is what happened. And if you find there is decent friction on the screw head, just return it to the position where you found it.

If you plan to use the radio for long at all, you need a spare relay anyway even if the relay in it is still okay. They eventually wear out. And if yours has a 4-digit date code stamped on it that begins with the digits "75", "76" or "77", it's probably factory original. It's rare to see that relay last more than 40 years.

Really rare.

73
 
Last edited:
  • Like
Reactions: Dmans
Thanks Nomadradio, I checked the c706. it was almost all the way tight clockwise from the back of the chassis. so i turned it out ccw ftbc about one turn. It didnt change or stop the spike. but It did bring up the output. i have not found the date on the relay it looks like it may have been replaced. im going to swap out the relay and see what happens.
 
I swapped out the relay. but, no change. I noticed when i key the relay engages, then the needle spikes hesitates and then it appears to throw the needle back toward zero.
 
i found the spike is on am also. It looks like its causing a full power spike on the watt meter.
 
Last edited:
Thanks Dman, I swapped out the relay, but its still spiking. Its transmitting the spike to my watt meter on ssb, and am but i do not hear anything on the monitor radio during the spike. The watt meter spikes to about 15 watts on ssb, then settles on zero. then it has good modulation. on am it swings to about 12watts and then settles on about 5watts. I can see the final tube glow blue for about a half second on ssb when it spikes
 
Thanks Dmans , I swapped out the final tube it still spikes on keyup so i put the newer one back in. i also checked the rf driver.
 

dxChat
Help Users
  • No one is chatting at the moment.
  • dxBot:
    Tucker442 has left the room.
  • @ BJ radionut:
    LIVE 10:00 AM EST :cool:
  • @ Charles Edwards:
    I'm looking for factory settings 1 through 59 for a AT 5555 n2 or AT500 M2 I only wrote down half the values feel like a idiot I need help will be appreciated