|
Post by wally on Dec 17, 2019 22:33:03 GMT -5
Well, I dont really understand this, but I started with a working transmitter, cleaned all tube sockets, channel selector, relay & controls. I replaced all capacitors, and checked & replaced all power resistors. I fired the transmitter up when done, no smoke or flames, and I have modulation but no carrier. I found 2 tubes that tested bad, 6GH8 & 6BQ5, so I replaced those, no change. Im going to go back over everything I did & make sure it is right per schematic, I was wondering if anyone would have any ideas on what is going on here? Thanks
|
|
|
Post by wally on Dec 17, 2019 22:34:02 GMT -5
Also forgot to add that voltages checked ok per schematic as well
|
|
|
Post by sgtpepper on Dec 18, 2019 9:05:39 GMT -5
Check the oscillator adjustments after replacing the 6GH8 tube.
|
|
|
Post by wally on Dec 18, 2019 22:16:05 GMT -5
Thank you for the reply, I am going to do that this weekend, my VTVM probe decided to break on me, so I need to fix that first. I appreciate your help
|
|
|
Post by sgtpepper on Dec 19, 2019 7:06:00 GMT -5
I forget to ask if it will spot in the receiver?
|
|
|
Post by wally on Dec 19, 2019 23:38:30 GMT -5
No, the spot isnt working now either, the spot light comes on but it will not send a tone to the receiver.
|
|
Sandbagger
Administrator/The Boss
Posts: 6,245
|
Post by Sandbagger on Dec 21, 2019 10:13:36 GMT -5
No, the spot isnt working now either, the spot light comes on but it will not send a tone to the receiver. That helps to narrow it down. If the spot isn't working either, that pretty much points to the oscillator as the culprit. Check different channels. You may just have a bad crystal. Other than that, I can't offer up an "a-HA!" thing to check. But focus on the oscillator area.
|
|
|
Post by wally on Dec 22, 2019 2:14:42 GMT -5
I started checking voltages again, I noticed that the voltage on the grid of V1 was much lower than stated on the schematic. I also noticed that the voltage would change by moving the pa/cb switch, and that switch is difficult to move. I am thinking of jumping the pa/cb switch out, and I am thinking it should bring the voltage up to where it needs to be. I will also check the oscillator circuit out, I did replace the 6GH8 oscillator, but that might not mean anything, but supposedly it was an NOS tube. I am slowly making progress, I appreciate the help.
|
|
|
Post by wally on Dec 24, 2019 1:06:07 GMT -5
Well, thats what I get for trusting a vendor to sell me a good tube. I bought a NOS 6gh8a that was supposedly tested, but it turns out it was not any good. I had a Courier 23 laying around, and it had 3 6gh8a tubes in it, so I used one of those, and the transmitter came back to life. Now I can move on to finish alignment on it, amazing how something simple can cause problems. Thank you all for the help, Im sure Ill need it again.
|
|
|
Post by Bigeagle on Jan 23, 2020 17:33:06 GMT -5
I have a 68r and 68t eagle i tested a tube it registered as good but it was not so tube checkers a not fool proof. Im having trouble with the auto on. Where you turn on the receiver and it turns on The Tx. Both turn on and off individually.
|
|