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

Thread Closed
Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

Philco 38-690 Troubleshooting.
#1

I am working on a Philco 38-690.

Can I test and troubleshoot the power / audio chassis WITHOUT connecting RF chassis to it?

Thank you,
nv3g
Oscar
#2

http://www.nostalgiaair.org/pagesbymodel...013255.pdf

If you look at the circuits in this radio, both power supplies are needed for the audio amp. The bottom one supplies the current for the driver and finals, and the top one supplies grid bias to the amp and B+ to the receiver. So you’ll need both power supplies running and all speakers hooked up to start with.

I don’t know what the bias voltages would be like with the top power supply not properly loaded. I suspect not correct. If that question could be answered by someone how did exactly what you want to try, we’ll know if anything will get damaged.

I get that it would keep the bench less cluttered while working on it. Other than that, not sure what would be gained.

Tony

“People may not remember how fast you did a job, but they will remember how well you did it”




Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
Atwater-Kent 84, restoration.
The wires were desoldered from the can, and the capacitors checked. All checked at 0.102 uF, which is correct. So the c...morzh — 09:41 PM
An attempt to remove the Field Coil from a G speaker
Arran Yours probably then the H speaker, same as mine.morzh — 08:39 PM
An attempt to remove the Field Coil from a G speaker
Mike; I would like to have a look at the speaker in my model 96, but the set is packed into a corner in the basement. ...Arran — 08:04 PM
91H Code 126 Restore
Thanks Arran, I'm convinced the power cord is good but have a nice repro plug for it. Would it be prudent to add a fus...RealRider — 07:28 PM
91H Code 126 Restore
As I was studying this schematic I was wondering what does this dotted line means?  I haven't traced it out yet. An o...RealRider — 07:22 PM
91H Code 126 Restore
When it comes to the cloth covered power cords, if they are not frayed, and are flexible, and if I can bend one without ...Arran — 06:21 PM
An attempt to remove the Field Coil from a G speaker
Could be. The central cylinder is OK, but the sides are...well. What's done is done. I wonder if some standard bobbine w...morzh — 06:02 PM
An attempt to remove the Field Coil from a G speaker
Mike; As I was saying it doesn't look like they used much of a bobbin for the field coil, not like a Magnavox one wou...Arran — 05:49 PM
Atwater-Kent 84, restoration.
This AK84 was bought, I think, last fall. For a whopping $100. It has been, according to the seller, restored. As I go ...morzh — 05:48 PM
Philco model 60
Plus I forgot that I have a spare complete Philco FC speaker, that would work perfectly, now that I don’t need it. Got i...Radios1340 — 05:36 PM

[-]
Who's Online
There are currently 2992 online users. [Complete List]
» 2 Member(s) | 2990 Guest(s)
AvatarAvatar

>