Welcome Guest! Be sure you know and follow the Phorum Rules before posting. Thank you and Enjoy! (January 12, 2025) x

Thread Closed

Grunow 654.. No Audio
#1

Just recapped.. turned on and at 100 Volts in draws 400 Ma..

B+ to ground is approx 310 Volts DC..

No audio.. When turning volume up and down get scratches.. No noticeable Hum..

Can scan schematic . Replaced the Bias cell with Watch battery.. Plus to Ground..

Skip
#2

OK Here are schematics..


[Image: https://farm5.staticflickr.com/4843/4518...c178_b.jpg]

[Image: https://farm5.staticflickr.com/4822/4518...af0e_b.jpg]


[Image: https://farm5.staticflickr.com/4828/4518...ee59_b.jpg]


OK  On second picture  The Black and Yellow leads were reversed.. I put them to match the schematic so the Resistance of field coil would be right.. Did I goof???

Skip
#3

When touching 2nd det cap or the output tube's grid, is there hum?
Are there voltages on plates?

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
#4

Ok  Stupid mistake again.. I forgot to install a resistor.. No voltage to OSC.. After install worked correctly..

Next Question  Where is the best spot to hook up my VTVM to measure the AVC Voltage?  Cannot get yo speaker voice coil to put on my output meter..

Skip




Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
54C Complete Teardown/Rebuild
Hello Roy, here is this one sincerely Richardradiorich — 12:45 AM
54C Complete Teardown/Rebuild
Richard, Had grabbed it already but thank you just the same.  I find myself wanting to find some way to block out the...glyphmon — 12:03 AM
54C Complete Teardown/Rebuild
Hello roy, here is a link to the schematic . Sincerely Richardradiorich — 11:54 PM
54C Complete Teardown/Rebuild
Richard, The Silvertone 2014 also is a transformerless set, so I am incorporating a 1:1 600 ohm audio isolation transfo...glyphmon — 11:37 PM
Preliminary work on wife's Silvertone 2014
Did an alignment today which was interesting.  IF alignment went great, almost all was already spot-on.  Adjusting on th...glyphmon — 11:35 PM
54C Complete Teardown/Rebuild
The main problem with adding a Bluetooth input is that this set lacks a traditional power transformer to isolate it from...radiorich — 11:19 PM
54C Cabinet Refinish
I started stripping this cabinet before it got super chilly out because I knew I wasn't going to be able to work on ...glyphmon — 11:18 PM
54C Complete Teardown/Rebuild
While I'm waiting to wrap up the final steps on my wife's Silvertone 2014, I started disassembly on the next project.  O...glyphmon — 11:07 PM
Preliminary work on wife's Silvertone 2014
Hello roy, that great news glad it worked out for you !! Sincerely Richardradiorich — 10:50 PM
Preliminary work on wife's Silvertone 2014
Safety caps arrived today.  Soldered one in and had a successful first power-up.  No magic smoke escaped and it tunes in...glyphmon — 09:53 PM

[-]
Who's Online
There are currently no members online.

>