Tram died again!

[frogman]

Heard a small pop under the radio and now the recieve is gone.I thought I got the 100,000 mile tune-up .

[Sandbagger]

Nov 5, 2008 14:00:22 GMT -5 frogman said:

Heard a small pop under the radio and now the recieve is gone.I thought I got the 100,000 mile tune-up .

Maybe it was only the 99,000 mile tune-up ;D

[2600]

Dontcha just hate it when it does that?

Your first, best tool is the calibrated eyeball. Any failure that makes a noise loud enough to hear should cause some kind of visible damage.

Should.

But even if you spot a part with visible damage, that may not be the whole story. But it's a start.

Which "Tram" radio is this? Kinda like "My Ford won't start". Might be a farm tractor, an over-the-road tractor, a Lincoln Mark 7, or a 4-door Escort.

And if it's a D201, which one? That model number narrows you down to roughly five different radios with that model number.

73

[frogman]

Its a 201 23 channel made in New Hampshire.It was working today but the s-meter stays all the way to the right.I could hear people and they were giving me good reports.

[frogman]

For the price I paid,it better have been the 100,000

[Marc]

But That only covers the parts that were replaced. Prob a small resistor or diode that was not changed out.

[husker]

Nov 6, 2008 14:53:21 GMT -5 frogman said:

For the price I paid,it better have been the 100,000

Yo know, when you make other items in the radio stronger, it just pushes the issues/breaks to another point..Fix one thing and another fails...that's why I keep ALOT of parts on hand for all my Trams......remember they are over 30 yrs old.

[Marc]

They call it the cascade effect.

See it all the time on old cars.

you fix a part then one a little farther down the line goes out.

Hi Husker

[2600]

So, this narrows us down to two radios.

The open-chassis New Hampshire radio, or

The circuit-board New Hampshire radio.

Both of these have the "diamond" logo on the speaker sticker.

Does it transmit? You didn't say.

73

[frogman]

It is now transmitting and receiving.Only problem now is the S-meter is pegged to the right.

[2600]

V602 and V401 are both 6GH8A tubes. One half of each tube is used to drive the meter. If one tube gets weaker than the other, the meter-zero trimpot will not set.

If you switch the tubes in these two sockets, one for the other, see if the meter now pegs in the opposite direction.

If so, this is a tube problem. The meter zero will be most stable if those two tubes are well matched. Replacing both at the same time with the same brand tube is usually the best bet to get the meter-zero setting stable.

Using one new tube and one old for these two tubes may prevent the meter from setting to zero, or cause the zero to drift constantly.

73

[frogman]

I replaced those tubes about 7-8 months ago.I can see the spark under the radio when I first turn it on.After it warms up,it goes away.I zeroed the meter works fine on AM,but it is dead on ssb although I can transmit,and recieve well.Looks like a diode needs changed.Also,I do not have a diamond on my speaker.

[Tombstone (R.I.P.)]

Sounds like a cracked, broken, or fried resistor, should be easy to spot if it is.

Tombstone

[2600]

SPARKS?

Not a good sign, ever.

You need to turn the radio on its side with the bottom cover removed and see where those sparks are coming from.

It's a good bet that whatever is making sparks either has to be replaced, or maybe get soldered down properly.

Sparks are always a bad sign, and NOT a standard 'feature' of this radio.

Just use proper precautions. The voltages in a D201 are sufficient to loosen the fillings in your teeth, or knock you sideways. Maybe permanently.

73

[Deleted]

The problem I had with 400 is that it's solid center and stiff as a 2x4. That Davis RF Bury-Flex is fantastic.