Philco 80 open coils - Printable Version

+- The PHILCO Phorum (https://philcoradio.com/phorum)
+-- Forum: Philco Radio Discussions (https://philcoradio.com/phorum/forumdisplay.php?fid=5)
+--- Forum: Philco Electronic Restoration (https://philcoradio.com/phorum/forumdisplay.php?fid=8)
+--- Thread: Philco 80 open coils (/showthread.php?tid=13185)

---

RE: Philco 80 open coils - bastardbus - 09-27-2015

Quick update and more interesting info. 

As mentioned I have been running this 80 in my shop down in the basement, with a 20 ft antenna and ground to a copper pipe.  I have been getting in AM 1370, 1230 anything high end of the dial coming in STRONG and great but 800 and 760 (stations usually equal to 1370) where fairly weak,  like 60%.

So curious about my correct IF I took the radio to check the LO with the only digital radio I have in my car out in the garage.  So I set the 80 next to the car antenna, hook up the 80 antenna (but with NO ground) and turn it on AM 800 so I can get a nice 450 or 460 above that easily.  Well BLOW ME OVER....that AM 800 was SOOOO strong and clear as was 760 it knocked my socks off!!  I go to try 1370 and 1230 and ffffftttttt NOTHING....or almost nothing.   I'll be d**ned!  LOL....

Long short my LO seems to be 460 and I take the radio back down to the basement and the previous set up and voila it is back to strong on 1370 and weak ish on 800 again.

So any ideas?  Is this just position and placement of the antenna?  Antenna length?   Could it be something with the antenna coil I re-wound? or is it just the nature of the beast being a 4 tube regen.

Looks like the fiddling around continues!

T

---

RE: Philco 80 open coils - Radioroslyn - 09-28-2015

Not sure  Sound like it could be an ant problem being too short. back in the day radio antennas where run 5 or 10' above the roof line of the house and perhaps 50' to 100' long. Generally speaking the longer and higher the better. A half wave antenna for the BCB be about 750' long. Being in the basement with 20' of antenna  and maybe steel studs doesn't bowed well for your antenna.

One way to troubleshoot this problem would be to inject a signal at various point across the dial and use an analog ac volt meter across the voice coil of the spkr to see if the gain drops across the band.

Perhaps a weak 36 too could cause this issue.

Something else to try is:
http://www.philcorepairbench.com/tips/svctip43.htm

Terry

---

RE: Philco 80 open coils - bastardbus - 09-28-2015

Terry, yes indeed I think antenna size-position etc had everything to do with it.  I have found with these old long wire receivers that every one of them sounds vastly different depending on the room an placement in my house.  We are in a new-temp home will we look for a new bigger place (just sold our house) so this house is foreign to me and have not been able to set much up yet.

Also, I did notice one of my 36s tested very near the top but the other was mid way so pondered that being an issue too.  I figure with a little set like this everything needs to be tip top shape.  I just purchased a matched pair of NOS RCA 36s on ebay for a good price so will have those soon.

Funny how one can seem to spend 3 times as much labor on a little set like this then a big complex one...

T 

---

RE: Philco 80 open coils - Radioroslyn - 10-01-2015

Just to be clear about the ant and ground connections, they won't cause the oscillator not to work but can cause the volume to operate properly on the Philco 80,81,and 84s and such With a short ant a gnd connection will probably cause a drop in signal strength. Most of the time it will lessen interference and improve selectivity..

Terry

---

RE: Philco 80 open coils - Radioroslyn - 10-02-2015

>I really like these little 80s. 
You should get an 81 it's the same set but has two bands!
Or the 84 Sound a bit better cause it has a larger spker.
84 came in several baby grand (cathedral) cabinets.
Terry

---