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One more thing - I could not help but notice the routing of that shielded cable in your 655.
The routing of that shielded power cable frankly surprises me. I did own a 655 once, many years ago, but I do not remember how its switch cable was routed. The routing of that cable in your set looks very sloppy. Maybe a Philco employee got lazy?
Anyway, I do remember that in model 16 sets, the shielded switch cable was routed along the side of the chassis, as far away from other components as possible, then along the front up to the volume control/power switch.
I hope you don't mind - I took the liberty of using your photo and added a crude drawing of my own below to illustrate what I mean.
The cable itself is shown as a thick red line.
The 18 gauge wires are thinner red lines.
The shield is a brown line, connected at the AC line bypass bakelite block (only).
If you do need to replace this shielded cable, I think I would route it as shown in the drawing. Just a suggestion. Yes, I know myself and others have told you not to re-route wiring, but this is an exception.
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Ron Ramirez
Ferdinand IN
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Thanks. That eBay cable is also foil shielded not braided. But the ground conductor is outside the foils, so it's in contact with the shields, and I can easily terminate THAT.
I'll have to look again at my old cables, maybe I'll get lucky!
BTW, I see that someone, likely my late brother, has been there before and worked on the power switch. I said the shield was only grounded on the other end, but now I see a pigtail on the shield was snipped off at the switch end... So it WAS grounded both ends...
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No, it wasn't - at least, not at the factory. Factory installed shielded switch cables have the ground connected only at the AC line bypass bakelite block end, not at the switch end.
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Ron Ramirez
Ferdinand IN
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Welp... I started with a radio that I could turn on and hear voices (from the speaker, not just inside my head)... but I knew that it wasn't all well.
Opened it up, saw the dripping e-cap, and decided to replace ALL the e-caps and paper caps, and all but one resistor.
I think I got it all back together right... turned it on, there was no smoke/flames/popping... but also no voices. Just BZZZZZZZZZ.
I know now that I committed at least one sin: I ripped everything out to rebuild all at once instead of replacing one cap at a time... and I THOUGHT I had recorded all the connections well enough. So while I'm reasonably sure I got it back as it was supposed to be, I could be wrong... or I could have knocked something else out of whack without realizing it... or it needs to be completely realigned...
All I can say for sure is that now I need to learn how to be a radio tech!
Starting with Elements of Radio Servicing (1947 ed.), and wondering how many tools I get to buy beyond my reasonably good VOM. We'll see!
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The 655 is re-capped, re-resistored, lightly rewired, re-aligned, and it functions, yay.
But in my area, AM reception is sparse, and where the radio must sit at home, there is no ground and few options for stringing antennas... so I want to add a minimally invasive Bluetooth device.
The 655 schematic shows a presumably optional (but not present on my unit) DPDT On-On switch for flipping between Radio and Phono. The switch, in Phono position, disconnects the 6A7 cathode from ground, grounds the detector AF output line, and sends the Phono signal to the volume control instead. Nice, I can substitute the Bluetooth line-out there and still use the 655's AF amplifier, staying mostly true to the Philco design intent.
Question: Anyone have images of how this was realized in production? Where the leads came out of the chassis?
My 655 chassis has one virgin knockout in back that could accept a 1/4" jack, or maybe a grommet for the required 4 wires to come out to an externally mounted switch. And with the phono, there should be an additional 2 power wires for the turntable.
Or... maybe the phono option was never offered, or only in Radiobar models?
(This post was last modified: 05-27-2023, 01:34 PM by patmat2350.)
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Perhaps a vintage add-on?
Regardless, I followed my 655 schematic, and it works great with my Bluetooth. I used my available knockout to bring the wires out, and with minimal and reversible mods inside. Sounds pretty clear with no static or hum, I'm happy. And happy I didn't set off fireworks ..
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Good job! And I think, it's been somewhat educational experience for you, so much the better.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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