46-1209 6v6gt hum and if question
Posts: 71
Threads: 18
Joined: Apr 2012
City: West Milford NJ
I seem to have a humm I traced to one of the 6v6gt tubes. I have done a full recap. Is it ok to run a ground wire from the socket ground to the chassis ? Also my radio is still not working I get no static or anything. I have a donor chassis and I was thinking of replacing the if's from that is that ok to do ?
Posts: 15,444
Threads: 539
Joined: Oct 2011
City: Jackson, NJ
Just do the really methodical troubleshoot. This way you will learn something.
What does it mean you traced the hum to the tube?
The ground is OK to run to chassis but why befopre it works?
Posts: 71
Threads: 18
Joined: Apr 2012
City: West Milford NJ
If I move that tube around the humm wil quite down. It always had a slight hum even after recap.
Posts: 15,444
Threads: 539
Joined: Oct 2011
City: Jackson, NJ
How can you "move the tube around" ? If the tube is in a socket it is immovable.
can you try to express your thoughts a bit more clear?
If you want help, we should not be guessing what you mean.
You should methodically explain what is going on, in good detail.
So far I did not see anything I can even try to start answering.
(This post was last modified: 03-13-2014, 09:14 PM by morzh.)
Posts: 71
Threads: 18
Joined: Apr 2012
City: West Milford NJ
Yes I understand I am new at this
Posts: 15,444
Threads: 539
Joined: Oct 2011
City: Jackson, NJ
1. Have you tested all your tubes?
2. Have you measured all your resistors and replaced those out of spec?
3. Inspected for bad wiring, shorts etc?
4. When does the hum appear, what kind of hum is it, does it depend on the volume control?
5. How do you move the tube around etc.
Speak English, spare no detail, don't speak in puzzles.
Posts: 239
Threads: 10
Joined: Dec 2013
City: Columbia, SC
If the noise goes away when you wiggle the tube, have you tried cleaning the socket pins? Sometimes they will make better contact if you squeeze the connectors together under the socket, with the tube removed. That works for bigger pin tubes, not sure about octals.
Posts: 1,092
Threads: 74
Joined: Jan 2014
City: Annapolis, IL
I vote for the socket contacts too. Have you tried a different 6v6? Could be a solder connection - it is easy to miss getting something soldered good if there is a lot of wires, or if there is oxidation on the new (or old) compenent, sometimes it wont solder good. Found this on other electronics before. I really dont think swapping parts, other than tubes is the answer. You may create more problems, and make it even harder to repair. You need to make some checks. Make sure you havent created a short with a ball of solder, bridged socket contact, etc. Do you have a schematic? Do you have a signal generator? You could have an open Rf/osc or IF coil. Check those. Sometimes an old radio isnt put into the attic for just one problem - often they start having small problems, then when things get to the point it no longer works, or the owner cant stand it anymore, it gets put up (or thrown away), so it may have several problems that will need worked through, plus any problems that happen while sitting.
If I could find the place called "Somewhere", I could find "Anything"
Tim
Jesus cried out and said, "Whoever believes in me , believes not in me but in him who sent me" John 12:44
Posts: 71
Threads: 18
Joined: Apr 2012
City: West Milford NJ
Ok I ran wire to ground the tube socket and no more humm
Still have no radio at all not even static I do not have a signal generator so I don't think I can do an alignment
Posts: 15,444
Threads: 539
Joined: Oct 2011
City: Jackson, NJ
Do the inspection.
Your 6V67 cathodes and filaments are grounded, check that.
See if you could pass the hum from tubes before bu touching the grids.
Although I am not sure what level of understanding you have in electronics, so you have to be really careful when touching stuff. Use an insulated screwdriver.
Posts: 1,092
Threads: 74
Joined: Jan 2014
City: Annapolis, IL
Usually you can touch something to the volume control lugs (the three that are next to each other in a row), such as a soldering iron, this is in the signal circuit, and should make a hum in the speaker if eveything beyond that point is working. If you get a loud hum, then your problem is before that point, and mostly eliminates the audio section. Do you know how to check voltages at tube sockets? Also, this set looks like it uses some loctal tubes, which are known for contact problems between the socket and tube pins. What part of the 6V6 socket did you ground?? Likewise, I dont know how much experiance you have with tube equipment, so I may ask some very basic questions. Did you power up the radio before the recap? If so, is this problem new or as before the recap?
If I could find the place called "Somewhere", I could find "Anything"
Tim
Jesus cried out and said, "Whoever believes in me , believes not in me but in him who sent me" John 12:44
(This post was last modified: 03-14-2014, 01:28 PM by TV MAN.)
Users browsing this thread: 1 Guest(s)
|
Recent Posts
|
PT-6 antenna connections
|
Hi Bridcarl
+1 on the others. Pin 6 of the 7C6 is the AVC Diode so it is appropriate that that pin 4 of the coil con...MrFixr55 — 07:30 AM |
462ron
|
Joseph, this is beyond awesome. A lot of thought and engineering went into this and you hit a home run! Now I must save ...462ron — 07:27 AM |
Cannot Adjust an IF Transformer’s cores
|
Outstanding work indeed. I wish I could come up with solutions like this.slford310 — 11:16 PM |
Cannot Adjust an IF Transformer’s cores
|
The abilities of our 'Phorum Pholks" never ceases to amaze me! Fantastic fabrication, Joseph! I'm waiting now for...GarySP — 08:27 PM |
PT-6 antenna connections
|
Thanks. I never realized that was a notch noted in the schematic as described. I’ll recheck my wiring.bridkarl — 08:13 PM |
Cannot Adjust an IF Transformer’s cores
|
Thank you! I was quite new to the Phorum when I started this post, so I feel like it might be advantageous to publish a ...jrblasde — 08:07 PM |
PT-6 antenna connections
|
Notice in the schematic the notch at the bottom of the antenna coil is between pins 3 & 4.
Yes, pin 6 of the 7C6 is...RodB — 07:34 PM |
bridkarl
|
I have two PT-6 chassis. On both there is a blue wire that runs from the above chassis transformer to pin 6 of 7C6. So t...bridkarl — 07:23 PM |
Cannot Adjust an IF Transformer’s cores
|
Joseph, now you are an engineer!!RodB — 06:37 PM |
PT-6 antenna connections
|
Hi, reading your explanation I can see the confusion. If you take it one connection at a time it should result in a desi...RodB — 06:34 PM |
Who's Online
|
There are currently no members online. |
|
![>](https://philcoradio.com/phorum/images/bootbb/asb/right_arrow.png)
|