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Retrofitting speaker for Philco 84
#6

Hi CtKid,

It is rather easy to replace this speaker with a modern one. Use a 1100 Ohm 10 W resistor (20 W would be better. a 1000 Ohm or 1200 Ohm resistor will be OK also. Please note that this resistor will get real hot, so place appropriately. I would not worry too much about "impedance matching" if using an 8 Ohm resistor. If the output transformer is bad, any transformer with a 7 KOhm to 8 KOhm primary and 8 Ohm Secondary will be good.

This radio is a surprisingly good performer considering the novel 4 tube "Superhet" circuit with no IF, an "Autodyne" 1st Detector (Oscillator Mixer) circuit and a "regenerative" 2nd Detector.

If the set does not work after replacing the speaker, "ohm" the Oscilloator coil. It is common that the "tickler" (the coil in the cathode circuit) is open.

This set is not as historically significant as the Model 20, 71, etc., but is a historically important set IMHO.
This set was originally produced, in the throes of the Great Depression, as a "Loss Leader" to get people into the showroom so the salesman could "upsell" the Customer to a more expensive, higher performance set. This failed, as people bought these sets big time and over 100,000 were produced, and the set was made in various forms and upgraded models until 1937 (The 37-84 was the same circuit but used Octal tubes). The original price was $19.95, and dropped to $14.95. This forced RCA to drop the price of their "loss leader" R28 set. Many companies and dealers were angered by Philco producing this set.

"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
Retrofitting speaker for Philco 84 - by Ctkid - 09-25-2022, 06:39 PM
RE: Retrofitting speaker for Philco 84 - by Ctkid - 09-26-2022, 09:57 PM
RE: Retrofitting speaker for Philco 84 - by MrFixr55 - 09-27-2022, 08:36 AM
462ron - by 462ron - 09-29-2022, 08:29 AM



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