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Philco 84b Weak Volume
#12

Jim, you're welcome.

The talent that is available on this site, especially from Ron Ramirez, RadioRoslyn, Paul Philco, Morzh, Aaron, Nathan, RFenstra, Phlogiston and many others (and sorry for not naming them) is unbelievable. Looking through some of the old posts that have pictures of some of their restorations, they are "phantastic".

Yours is a very interesting set. When I first started working a Model 80 (similar to yours), I thought it was a very simple TRF like the Emerson 25, RCA M-17 or other very cheap sets that popped up during the depression. After looking at the schematic, I was surprised to learn that it is a superheterodyne.

The key to the surprising performance of this set is the "regenerative detector". This is an old school grid- leak detector with a feedback circuit which causes a lot of gain. This is the basis for some of the original Armstrong 1914 patent 1 tube radios like the Westinghouse Aeriola Sr, one of the first commercially available "consumer" radios. Adjusting C17 adjusts the detector "gain before oscillation". Consideringthe poor fidelity and high distortion of grid-leak and regenerative detectors, this set sounds surprisingly well!

I find a lot or radios with good reception will get louder when one touches the loop antenna or, in the case of these older ones with grid caps, touching the grid cap. I guess our body mass makes a good tank circuit for the broadcast band. Based on my size, the lower end!

These sets really require a "long line" antenna of at least 25 ft horizontal length, along with a good ground. The antenna should point in the direction or exact 180 degree opposite direction to the desired stations.

Keep up this hobby of preserving the past. It is cheaper than restoring cars (Unless you get into some of the Atwater Kent Breadboards, EH Scotts, Zenith Stratospheres, Radiobars, RCA CT100 Merrill (first RCA Color TV), McIntosh HiFi, etc.)

"Do Justly, love Mercy and walk humbly with your God"- Micah 6:8
"Let us begin to do good"- St. Francis

Best Regards, 

MrFixr55


Messages In This Thread
Philco 84b Weak Volume - by percyjd - 10-15-2022, 05:13 PM
RE: Philco 84b Weak Volume - by MrFixr55 - 10-15-2022, 07:32 PM
RE: Philco 84b Weak Volume - by percyjd - 10-15-2022, 09:00 PM
RE: Philco 84b Weak Volume - by Radioroslyn - 10-15-2022, 09:02 PM
RE: Philco 84b Weak Volume - by percyjd - 10-15-2022, 09:37 PM
RE: Philco 84b Weak Volume - by Radioroslyn - 10-15-2022, 10:58 PM
RE: Philco 84b Weak Volume - by percyjd - 10-16-2022, 09:29 AM
RE: Philco 84b Weak Volume - by percyjd - 10-16-2022, 11:57 AM
RE: Philco 84b Weak Volume - by MrFixr55 - 10-17-2022, 08:14 AM
RE: Philco 84b Weak Volume - by percyjd - 10-17-2022, 04:51 PM
RE: Philco 84b Weak Volume - by radiorich - 10-17-2022, 04:59 PM
RE: Philco 84b Weak Volume - by MrFixr55 - 10-18-2022, 07:26 AM
RE: Philco 84b Weak Volume - by radiorich - 10-18-2022, 09:16 AM
RE: Philco 84b Weak Volume - by MrFixr55 - 10-18-2022, 02:32 PM
RE: Philco 84b Weak Volume - by percyjd - 10-18-2022, 08:21 PM



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