Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: shooter on September 11, 2022, 05:34:41 pm
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My Brother the scrounge, Tom can find things the store owners forgot they had :laugh:
This and him showed up today, told me it was stuck under a pile of junk, but he could see a tube n knew I messed with tube stuff!
The shop owner did forget it was there, let it go for $15. Bro took it home cleaned out all the debris, Gotta love a good brother!
no time to do anything for awhile except some inter-web surfing. I can already see it in the '02 dodge, or the camper with a shiny new 6vdc battery
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I have restored four 6v car radios and built one into a guitar amp.
Good fun projects. I always had trouble getting enough current to run the radios.
A rare one here
https://stillampd.com/motorola-car-radio
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Nice score Shooter
Franco
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paid a couple $'s, schematic should be here in a few days. tinkered some last night, noticed one tune coil has a missing /broke shaft, dial indicator don't move, one of the 6AQ6's was missing, had an untested spare so I filled the empty socket
PRR in another thread answered the mystery of why the 560 button "latched" besides being just on/off.
looks like there's enough room under the coil pack to stick in the guts from an old boom-box. use that to drive the PA section hanging off the back and still keep the original "looks"
I have NO desire to mess in the RF/IF section ever again :laugh:
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No schematic drawing SW, so it's a painted edit :laugh:
this'll be my start for raisin the dead
probably re-build the PS to something closer to a simple tube AC version
painting the PS next, 6X4, found an AC version using that tube, IIRC it was an early Gibson
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quicky PS sketch
thinking about mounting the radio on slide brackets, make some PS room behind the chassis
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since it's 22F and 20mph winds, time to strip the chassis
decided to go down to the metal, taken the pieces parts to a chop-uh-bodyshop down the road. The kid can bring old rust back with a shine.
the AM section is beyond hope, i'll work the new ac PS in that area, probably make one pushbutton work as on-off, the 2 knobs, volume and dummy.
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Pieces at the paint shop, ready mid Jan. Scraping the PA/PS, it just hangs off the back like a wart
The R-side of the main chassis has the right socket layout so, strippin down. Probably clean up the L-side components, couple dummy tubes.
The IF tuner will get gutted, cleaned, painted. run a long screw down the center and bolt a tag strip on the bottom.
OT will mount on main chassis, basically where the PA/PS hung.
Still thinking;
Build the PS on the left chassis, or inside the button chassis. The pushbuttons will get dummied up. Same with the dial indicator, 1360 AM. Was the rock station here in the stone age. Looks like I can cut in a 9 pin for the preamp tube, leaving the PA 7 pin for now.
More supplies, I’m out of wick, getting low on real solder.
Ballparking the total cost at 4 new ’55 Plymouth tires, set of plugs, wires, cap, rotor, full tank of gas…
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about an hr with 320
Since the faceplate is green, the Iron will be from Edcor, blue, makes sense the “wrap-around” metal is yellow. tape off the horizontal section. Once the weather breaks, might cut a piece of ¼” birch ply to fit in the “middle section” where the button chassis sat.
When I sprayed/wiped down the “dummy” leftover parts, got a smile from the cap maker.
While the paint dries, I’ll put together the shopping list.
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late to the party but I've done a few radios. I always go here first:
https://www.radiomuseum.org/r/philco_pd_4908.html
then here:
https://www.antiqueradios.com/forums/index.php
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was warm enough to open windows
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primed the cans, thinking just clearcoat the primer.
The bottom snippet is from my last build, back from the wild, driving an Audio mid-bass speaker.
probably start with stock, 6C4, maybe aim closer to original 105vdc - 90vdc, datasheet wants the 6AQ6's driven between 12-30Vac peak.
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the shop finally, finished striping down all the hi-end cars, so they got to my radio :icon_biggrin:
just as the weather is great for playing OUTSIDE!
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Rodney Crowell - 56 Fury - YouTube (https://www.youtube.com/watch?v=SlXyATQAKaU)
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"bilt for speed...
...with every last thing you need" - BillyG
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I smell fall in the air, so...
I ohmed the lights on the dial indicator, got 3 ohms, the B+ was 6vdc, does 2A seem normal?
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Each #47 is rated 6.3V @ 0.15A.
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Incandescent lamps are not constant resistors. The cold resistance may be 1/10th of the hot resistance.
10 times 3r would be 30r, 0.2A. That is not exactly 2*0.15A rated. The "10X rule" is a gross approximation, almost just a warning. It semi-explains why incandescents typically burn-out at turn-on.
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once Steve gave me the specs, figured there must be a thermal element in the math.
scrounging a 6vdc ps soon
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I have restored four 6v car radios and built one into a guitar amp.
Good fun projects. I always had trouble getting enough current to run the radios.
A rare one here
https://stillampd.com/motorola-car-radio (https://stillampd.com/motorola-car-radio)
That site seems to be compromised.
Respectfully,
--Pete
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Rodney Crowell - 56 Fury - YouTube (https://www.youtube.com/watch?v=SlXyATQAKaU)
This one is my fav... Apologies for the topic deviation.
--Pete
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worth the diversion, thanks
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https://stillampd.com/motorola-car-radio (https://stillampd.com/motorola-car-radio)
That site seems to be compromised.
FireFox on Windows is not throwing any warning for me.
I note that the certificate will expire this week. But not today. And a Let'sEncrypt cert normally auto-renews?
(Yes, I know Music Electronics Forum and its renewal troubles.)
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I have restored four 6v car radios and built one into a guitar amp.
Good fun projects. I always had trouble getting enough current to run the radios.
A rare one here
https://stillampd.com/motorola-car-radio (https://stillampd.com/motorola-car-radio)
That site seems to be compromised.
Respectfully,
--Pete
It was down for a bit. But is back up now.