Posts: 825
Threads: 113
Joined: Aug 2012
City: The Villages
State, Province, Country: Florida
Ok, I know it was a mistake, but I strayed from Philco. I picked up a Grunow 588. I got it for only $38.00, but now I'm stuck.
I replaced (very carefully) all the electrolytics and paper caps as well as any resistors that were out of range. The tubes were tested and replaced as necessary. All I get is a low hum. I get nothing if I touch the center lug on the vol control.
Any ideas?
Thanks,
Eric
Eric
The Villages, FL
Member: Philco Phorum, ARF, ARCI & Radiomuseum.org
Posts: 2,128
Threads: 18
Joined: Oct 2008
City: Merrick, Long Island, NY
Schematic here I think this is your set :
http://www.nostalgiaair.org/PagesByModel...008378.pdf
You may be able to scare up a clearer image and more information elswhere
I'd check the plate voltages (measure to B- rail) and make sure the output transformer and field winding is good and and wiring is OK. Well, then it's just a mater of working backwards from the speaker to find the point of failure. Frankly I wouldn't trust any of the carbon resistors in a set this old, no matter how they measured cold.
Posts: 825
Threads: 113
Joined: Aug 2012
City: The Villages
State, Province, Country: Florida
Thanks, I'll check these and get back to you.
Eric
The Villages, FL
Member: Philco Phorum, ARF, ARCI & Radiomuseum.org
Posts: 825
Threads: 113
Joined: Aug 2012
City: The Villages
State, Province, Country: Florida
Time to show my ignorance/inexperience. What is the B- bar? Isn't it just ground on the chassis? This is an A/C radio.
From what I've found so far the plate voltages are all there but I can't seem to get any filament voltage readings but the tubes are hot. Any thoughts?
Thanks,
Eric
Eric
The Villages, FL
Member: Philco Phorum, ARF, ARCI & Radiomuseum.org
Posts: 7,286
Threads: 268
Joined: Dec 2009
City: Roslyn Pa
It would be the center tap of the HV winding of the power transformer.
Terry
Posts: 825
Threads: 113
Joined: Aug 2012
City: The Villages
State, Province, Country: Florida
Hey Guys,
I got ot working! What a great feeling. I wish I could tell you exactly what I did but I can't. All I did was take out the tubes and retested each one. Turned it on and it works great. Just aligned it and it pulls in stations really well. BC and SW.
Thanks for everyone's help,
Eric
Eric
The Villages, FL
Member: Philco Phorum, ARF, ARCI & Radiomuseum.org
Posts: 2,128
Threads: 18
Joined: Oct 2008
City: Merrick, Long Island, NY