I picked up a near mint P850B for $15 that came complete with a case, earphone, warranty/registration card. The thing is collector's quality.

I replaced all 3 electrolytics. The radio takes a 4.5V battery, which I do not have, so I am using a power supply. I have very low audio. I can barely pick up a couple stations, and have something intermittent as audio comes and goes.

Also, the audio seems to come and go into a bird chirp. This radio is very small and a service nightmare. I resoldered some joints.

Any ideas on this? I can scan my SAMS photofact if you need to see it.

Can suply the sch ?

correo@candiles.org

http://www.mediafire.com/?wdghd840dk16748

Here you go.

Hi, thaks by sch.

Try to clean ON/off and Earphone socket.
The volume are good on earphone ?
Try onother spare speaker in lieu of original.

The volume control looks difficult to spray without outright removal. I did spray earphone plug. The speaker is 45 ohms. I do not have anything near that.

Have one osciloscope ? can see Vpp at speaker to see if problem are signal or speaker.

actuate ear jack with small philips screwdriver. burnish contact with flat jewelers screwdriver or burnishing tool. continuity check everything that should have resistance

I got it working where it is picking up a couple stations, but volume is still low. Intermittent problem is gone. But This is collector's quality, so I am going to dump it and put the money to another radio I can use or restore. I really have no use for this. I only picked it up because I figured that some collector might want it. I would rather put the money to a vintage SW or AM DXer radio. I just finished up a Knight Star Roamer that sits nicely in my shack.

I haven't seen the print, but if this is a five or six Transistor set, it should have four Electrolytics, and trust me, it's always that last one...

Also, you might try just slightly tweaking the IF cans (not the oscillator though...It's marked in red).

AFA the earphone jack, that's either a go or no-go; it completes the speaker circuit or it doesn't. It won't affect the volume level, and doubtful cause an intermittent.

You may have paid full "market value" for it.

Actually, the GE P850B uses only 3 electrolytic caps...C1 (8 uf - AVC filter/timing), C2 (3 uf - audio coupling), and C3 (40 uf - PS bypass).

Dave

I replaced the 8uf with a 10uf. I could not find anything close to 8uf.

10 close enough. 47 will work OK for the 40 and a 4.7 for the 3 if you can't find a 3.3.

From the schematic, you have a speaker/output transformer combination. 45 ohms are the transformer windings resistance. This could be bad. Try an earphone in the earphione jack. If it's good listening volume, then the speaker is the culprit. Some of these types have had the magnet material degrade into a loose powder with poor output. It happened to me on a P945. Good luck finding a replacement. Ken