Voltages of "A" and "B" batteries
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City: Cashmere WA
Hello everyone,
I have the Philco model # E 676 124 shown below; and can't seem to find out what the voltages of the "A" and "B" batteries are supposed to be. The sticker in the back of my radio says the "A" battery is type P31, and the "B" battery is type P190.
I haven't found a cross reference for these battery numbers to Eveready, or any other manufacturer.
The 4 tubes in the radio are 1R5, 1U4, 1U5 and 3V4. I read somewhere that the "A" battery voltage could be determined by adding up the first numbers of each tube (Heater voltage). I haven't determined the "B" battery voltage, but the data sheet(s) on the tubes may indicate this, as it is supposed to be the tube's plate voltage.
What I'd really like to have is the specs on these original batteries, and would be happy to buy dead originals that I could re-stuff or otherwise "counterfeit". Lastly, I'd HATE to guess wrong on the voltages and lose tubes, caps, etc.!
Thanks in advance for the help!
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City: Roslyn Pa
Hi Dan and welcome,
http://www.rsp-italy.it/Electronics/Radi...n/1957.pdf
See pg 95.
Looks like your looking for a 7.5v A battery and a 90v B battery. These batteries haven't been around for 30 or 40 yrs now so you'll need to build one to operate it from DC power.
When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!
Terry
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City: Sandwick, BC, CA
It looks like a three way portable, that would explain why the tubes filaments are arranged in series. On older portables they would often switch the filaments between series and parallel arrangements so you could run the set off of a more normal 1.5 volt "A" battery, but by the 1950s they didn't bother with that as much.
Regards
Arran
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City: Cashmere WA
Thank you, guys! The link was a BIG help. I didn't expect to get detailed alignment instructions, too. This little piece of history is going to sound the same as the day it was built, when my replacement 1U5 tube gets here.
I did finally track down a guy with a YouTube channel that goes by the name "batterymaker", and eventually found the dimensions of the batteries.
I've seen the term "three way portable" a few times now, what does it mean?
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City: Roslyn Pa
That's why we are here, Philcos are our specialty!
3way power is a reference to the fact that you can power it from 117v ac 117v dc or batteries. Sales buzz word. If you poke around enough you may find the graphics for your batteries too.
When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!
Terry
(This post was last modified: 03-12-2017, 02:36 PM by Radioroslyn.)
Posts: 7,212
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City: Roslyn Pa
Hey Dan,
I was cleaning up some old files in my hd and found this:
http://radionostalgia.club/lib/Images/battery/Unsorted/
May find a usable image.
When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!
Terry
Posts: 4,603
Threads: 50
Joined: Sep 2008
City: Sandwick, BC, CA
(03-12-2017, 02:33 PM)Radioroslyn Wrote: 3way power is a reference to the fact that you can power it from 117v ac 117v dc or batteries. Sales buzz word.
I think that it was pretty much a sales pitch, at one time it was relevant as there were DC mains power grids in places like down town N.Y.C, it's the same with most transformerless series string sets, commonly referred to as AC/DC sets in their marketing. I would guess that even back in the 1930s having to deal with a DC power grid was only of concern to probably 5% of their customers, but it sounds better in marketing then promoting a set as being cut rate thanks to the omission of a power transformer. Believe it or not I have seen tube, battery portables with a power transformer, but they were either British or European made, not North American made.
Regards
Arran
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City: Wellborn Florida
Here is a picture of the sch. David
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City: Cashmere WA
Thank you, everyone! 
The first order of business is to get my radio in working order. I'm (somewhat impatiently  ) waiting for the arrival of a replacement 1U5 tube, and then I can at least plug it in.
There's a paper cap that may have failed, due to age and the fact that it is a paper cap, but I plan to power the radio up with a 100W light bulb in line with the radio's power cord (see note below). So maybe the cap will "recondition" before it just blows up and I have to spend Saturday vacuuming the remains of a paper cap out of the chassis... one can hope.
I'm a newbie, so if anyone sees a glaring flaw in my plan, PLEASE RESPOND BEFORE FRIDAY NIGHT... assuming my new tube has arrived!
I did spend a pleasant (?!) last Saturday vacuuming the remains of a few dead spiders and their webs out of this particular radio. I took the first layer of crud (patina?) off of the radio, inside and out.
The Note below: Having read through several sources, adding a 100W light bulb in series with the 120 volt AC cord will prevent a catastrophic failure, if a capacitor is shorted. If a cap DOES short, the light bulb will glow brightly, indicating that there is no, or very little, voltage drop across the radio being tested. The light bulb acts as a ballast resistor.
Ideally, the bulb will glow somewhat less than one would expect a 100W bulb to glow, when connected across 117V household voltage. Radio performance will be impaired, but this is simply to test that there are no short circuits present.
One last bit about me; I'm an electrician by trade. I got a 2 year degree in Electronics Engineering in the mid 1980's; in fact, I got the tail end of Vacuum Tube Theory (the next class didn't get it). That's how this hobby originally got a grip on me. My grandparents had a few radios that I inherited, and I collected 2 or 3 more at garage sales.
Finally, just after I turn 50, time and money came together and presented me with the opportunity to get these radios working again!
I'm putting together A and B battery packs that I think will fit in this radio chassis. The A battery (that I'm doing) is a little bit bigger than the specs I found, but I think it will fit in my radio. I plan to use 10 AA batteries, 5 stacks of two batteries each. I'll wrap them with the period correct battery labels later if all goes well.
The B battery is very straightforward: the 10 batteries I salvaged out of smoke detectors can be series'ed (sp?) together at least long enough that I'll know that part of the radio is good! That was the easiest battery to figure out, the 10 9V cells will easily fit in the original battery dimensions, to spare.
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Personally I wouldn't bother trying to reform the electrolytic caps in your set. Just replace them there is 3 of them. You won't be able to find an original style one these days but you can make a replacement. Like the batteries you can build one that is suitable.
Posts a few pics of the innards of your set. The new caps are much smaller in physical size than the old ones. This makes the job pretty easy.
When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!
Terry
Posts: 19
Threads: 5
Joined: Mar 2017
City: Cashmere WA
Thanks everyone, I hope to post a few pics this weekend. The chassis itself looks to be in good shape overall, it's mainly the leather case and missing knob that need the most attention.
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City: Holiday TN
Lately I have been thinking (always a dangerous thing  ) and doing the caps a bit different.
I've tested the old caps I pulled out for years just for
Can't say I remember finding a bad paper foil cap. Even the ones that had been stored in hot places and most or all the bees wax sealing the ends had run out and made a mess. Still tested fine for cap and no leakage at stated WV. Same goes for the plastic enclosed paper foil even with the plastic cracked.
The electrolytics are different. Some good some bad. I got to thinking about the "standard" procedure of using a Variac to slowly bring up voltage to reform them. That is the "way" most of us have done it for years without ever thinking about it.
With rectifier tubes there is no DC to reform the caps till filament voltage get high enough for the tube to start conducting and then there is too much voltage available.
The radio posted above would OK for reforming caps with a Variac - solid state rectifiers.
Just did a 1946  Zenith AC/DC AM with 78 player.
Rectifier was a 35W4
Used a variable voltage DC supply to reform the 3 section cap. Several days at 5 or 10 volts then slowly over a day or so to section rating. Tubes were out and it was easy to pop 1 or 2 wires to test the cap. All 3 section were + 10 to 20% on capacitance and ESR was lower than new GP electrolytic.
The paper foil caps were replaced because all the bees wax had melted out. They were all 10 to 20% above cap rating and no leakage at rated WV. Note: Old caps were almost always over min cap rating.
Also finished up a Weston 981 Type 3. The old larger electrolytics same story, but in this case were replaced anyway. I am guessing the tube tester had been stored in a damp place and the Sprague orange cardboard / paper covers were mildewed and it is crowded in between the TBs. Modern GP caps are a LOT smaller and freed up a lot of room. There was a bad 25MF @ 25V - Cornell Dubilier (good brand) guessing it dried out. The red + end seal is HARD.
Cap testers have gotten CHEAP.
I am about to break into a Motorola communications test set. I expect to find most of the PS caps good like the last ones I did. Old habits die hard - I am planning on replacing the smaller caps like usual. Not worth reforming and testing to save a few pennies and traces on boards do not like to be desoldered too many times.
Just something to ponder
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(03-12-2017, 07:07 PM)Radioroslyn Wrote: http://radionostalgia.club/lib/Images/battery/Unsorted/
Hey Terry, thanks for the link. I can use it. I've spent hours in MS Paint touching up photos of a Silvertone 45 volt battery for the same reason of creating a new one.
Dennis
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Joined: Mar 2017
City: Cashmere WA
At the risk of this thread running too far off topic, I powered my radio up this week, since I simply lost patience trying to get the proper caps before I light her up for the first time in what is undoubtedly decades.
The good news is that after taking it apart far enough to check the caps, it seemed reasonable to try it. The caps weren't open or shorted. I plugged it in and tried it. After the tubes warmed up (2 to 5 sec. , forgot about that...) it played great!
560 KPQ comes in as clear as a bell, plus several others. Oh yeah, I'm adding stuff to make this thread pop up in the Search function, so forgive me if it seems if I'm typing some gibberish in. (See below)
1957 Mustang, E 676 124, E 675, (PLEASE add anything else you think might help a searcher find this!). I've found that a few other model numbers have shared this chassis.
I still plan to get the pictures posted. Got to get some help from my daughter, as she owns the digital camera that will be used to document all of this.
I found the 3 caps mentioned, plus the 3 caps in a single can that are listed as [250uf @ 10V, 60uf @ 150V, 80uf @ 150V].
In my radio, the three paper caps were: 0.22uF 100V, 0.047uF 200V, ad 0.047uF 400V. The first 2 caps were axial lead caps, the last one was a radial lead cap. I'll point them out in the future photos.
Not referring to Philco's in particular, but I've noticed that a few manufacturer's schematics seem to be more of a guideline than a solid representation of the components used to build the radio in question. I'm still pretty new to this hobby, so please forgive me if I babble on about common knowledge. As stated, I'm trying to make this thread come up in a Search for others who may have one of the aforementioned radios / chassis.
About "A" and "B" batteries; THANK YOU Radioroslyn an David!
It's a lot easier to convince the wife I should spend money on a Working radio than a Dead one...
5 pairs of AA batteries should just fit in the area meant for the 7.5 Volt "A" battery, they may be 1/8" over the original battery. More to follow.
The "B" battery space will easily accommodate a stack of ten 9V batteries; I just need to come up with the proper connector to fit that wider spaced 90V battery connector in my Philco. Maybe I'll buy dead batteries off of eBay, or possibly gut and re-purpose some dead 9V battery parts.
Whatever I do, I'll document it for those that run across this thread and hopefully we can pass on some useful information. Incidentally, when Searching for "Philco E 676 124" on Bing, this thread popped up on the first page; just sayin'...
In the meantime, I'll be out in my shop, working on my truck and listening to the radio...
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