04-05-2019, 08:32 PM
(04-05-2019, 07:49 PM)RodB Wrote: [ -> ]Now I need the alignment instructions for the Philco 511, 512, 513, 514 or 515 and maybe the 86 would work.
https://philcoradio.com/library/index.ph...receivers/
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04-05-2019, 08:32 PM
04-12-2019, 12:42 PM
Thank you Ron. I figured it was here somewhere, just have to use the right keyword ("alignment" doesn't work). Your set of instructions are much better than the basic ones I found elsewhere.
So, I have had a change in direction on the speaker. Instead of the re-cone job the owner has decided to go with a PM speaker mounted in place of the cone. I have located an 8 ohm, 8 inch, full range driver to connect to an output transformer. To check this configuration, I used my test speaker connected to a universal OT and tested the output of each of the 6 transformer speaker lugs. The output is now so loud I can't turn it down with the volume control. The set also oscillates at various positions of the dial. I'm thinking there's too much gain and maybe reducing the B+ might fix that. The 10K volume pot. also might be a problem. More testing to resume.
So, I have had a change in direction on the speaker. Instead of the re-cone job the owner has decided to go with a PM speaker mounted in place of the cone. I have located an 8 ohm, 8 inch, full range driver to connect to an output transformer. To check this configuration, I used my test speaker connected to a universal OT and tested the output of each of the 6 transformer speaker lugs. The output is now so loud I can't turn it down with the volume control. The set also oscillates at various positions of the dial. I'm thinking there's too much gain and maybe reducing the B+ might fix that. The 10K volume pot. also might be a problem. More testing to resume.
04-12-2019, 01:10 PM
About that oscillation: have you neutralized the set?
04-15-2019, 12:25 PM
I haven't neutralized the RF sections yet, I have a few things to take care of first. I checked the B+ voltages and they are higher than documented recordings and the filament voltages are slightly higher. So I increased the primary dropping resistor value from 9 ohms to 34 ohms. This brought the voltage on the 90 year old primary winding to 112V and the B+ and filament voltages to where they should be. I discovered the 10K volume control to be erratic so I'll have to replace it. Without the control in the circuit the volume is very loud.
I want to get all the component issues out of the way then fasten the bottom to the chassis then do the neutralization because I noticed whenever I get close to the chassis with my hand the signal strength gets noticeably stronger.
Rod
I want to get all the component issues out of the way then fasten the bottom to the chassis then do the neutralization because I noticed whenever I get close to the chassis with my hand the signal strength gets noticeably stronger.
Rod
04-15-2019, 07:20 PM
< I get close to the chassis with my hand the signal strength gets noticeably stronger.
Do you have the chassis grounded to something? Not having a ground connected to it can cause this anomaly.
GL
Do you have the chassis grounded to something? Not having a ground connected to it can cause this anomaly.
GL
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