Tram D201 40yr/100 Mile Restoration Done Right

[bucketofguts]

Remove that wire. It makes more power out but lowers modulation and kills your radio.

In my journey watching Mike and tramdr I am slowly finding out such things. It has been clipped/removed. Thank you for you help!

 

[nomadradio]

What is this coax doing on the vox pot?

I think someone was desperate to reduce the AC hum on the mike audio. Shielding the output lug's wire on the mike gain control sounds logical, but won't help.

Seems to me I posted the procedure with pics to fix this. The heater for this tube is grounded to the socket's saddle ring. This causes a tiny 60-Hz voltage drop that is added to the mike audio feeding into this tube.

Pretty sure pin 5 of V601 is 6.3 VAC, and pin 4 is ground. We gently unsolder pin 4, and re-route the ground wire that passes through the lug's eye. Now that the lug for pin 4 is isolated, a wire is soldered to it. A plastic sleeve over the lug may or may not seem wise to make sure it's insulated from touching any nearby grounded metal. The other end of the wire is grounded at the rear of the chassis where the power transformer's heater-winding has one wire grounded.

This eliminates the 60 Hz current flow through the rivets holding the socket for V601, and prevents it from being amplified by the mike amp.

Somewhere in this forum I think there is a post for this with pics.

73

 

[bucketofguts]

Thank you for the reply. I think you are right on the $. I will search for the procedure with pics to fix that issue. Thank you very much for taking the time.

73 back to ya,

b~

 

[bucketofguts]

I need a picture of the board in the center of a hand wired Tram D201. From the top of the unit. I replacing the caps 4 caps and i cant make out the +/- on the caps. thank you in advance!

b~

 

[bucketofguts]

This is how I installed the caps so far. Please tell where I need to change the polarity. Much obliged.

b~

 

[tramd]

Here is a diagram from the circuit board D201manual. The board is the same as the vox radio's board, except the vox board used round sockets and pins and the later D201 and D201A used square ones. The diagram clearly shows the orientation of the caps.

 

[bucketofguts]

Anybody have a PW15 W 2.7K

Here is a diagram from the circuit board D201manual. The board is the same as the vox radio's board, except the vox board used round sockets and pins and the later D201 and D201A used square ones. The diagram clearly shows the orientation of the

Here is a diagram from the circuit board D201manual. The board is the same as the vox radio's board, except the vox board used round sockets and pins and the later D201 and D201A used square ones. The diagram clearly shows the orientation of the caps.

 

[bucketofguts]

Anybody have a PW15 W 2.7K

Here is a diagram from the circuit board D201manual. The board is the same as the vox radio's board, except the vox board used round sockets and pins and the later D201 and D201A used square ones. The diagram clearly shows the orientation of the caps.

Thank you! Yes it does make it quite clear. Thank you for taking the time.

 

[bucketofguts]

Here we go again. Is this Hitachi Silicon Power Transistor?, missing a leg. If so where does it go? Thank you in advance,

 

[bucketofguts]

If so is this the same animal?

 

[tramd]

Here we go again. Is this Hitachi Silicon Power Transistor?, missing a leg. If so where does it go? Thank you in advance,

The leg is missing because it's not needed. The leg and the metal tab of the transistor are connected, so there is no need for the leg. This is used as the regulator for the 14 vdc circuits. If you measure about 14.2 vdc on the output of that part which is the emitter, it is okay. The emitter is the right-hand side leg. The center leg is the base and should be about 14.7 vdc. The left-hand side is the collector and is the input at about 25 vdc.

 

[bucketofguts]

Thank you again! Mine is getting new a makeover. I will be for a while.

 

[bucketofguts]

Broke a diode. Says GT005 I think. What do I need to order. Center of the pic. Thank you for your help!

 

[nomadradio]

It's a generic 1-Amp rectifier diode. Type 1N4007 is a more-modern type number, easy to find.

73

 

[bucketofguts]

Thank you very much!

​