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Hi,
I'm new to this forum - thanks for letting me come aboard!! A few months back I acquired a 41-788 and have just started looking into it. First off - the speaker was missing but I have an equivalent electrodynamic speaker that I can use to get it up and running.
My first concern is the e-caps.... there are 2 cans - one is a multisection labelled with values of 40uF, 5uF and 5uF. For the life of me, I can find only the 40 and one 5 referenced on the schematic - where's the other 5 ???
The other can is covered with silvered paper - for insulation I suppose - and I can see no values on it. I assume it's the 16uF shown on the schematic - but it has 3 terminals. Does anyone know how this cap is set up???
And, finally, I have a 10" PM speaker I will eventually use in this radio. What is the best way to allow for the lack of a field coil - should I simply sub in a power resistor and up the value of the filters caps - or do I need a choke too.... and what values would I be looking at trying to find???
Thanks.....
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Hellooooooo (prolonged echo).......Anybody here  : : : 
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I'm here but don't have a lot of time, busy with college.
Anyway...welcome! The 41-788 is a desirable radio and should be a really good performer once restored. I have one of those and its near twin, the 42-788.
One of the 5 uF caps (13A) is in the set's front end; it connects to a line going to the screen grid of the RF amp tube 7C7E.
The other 5 uF cap (13B) is in the audio circuit, connected to the junction of resistors (74), (78), (79) and (87).
The only other electrolytic I see is (88), and it should be a single section electrolytic. Maybe yours has been replaced with a dual or triple section twist-lock, and only one terminal was used?
These 1941 Tropic models were perhaps the first Philcos to use twist-lock electrolytics, which became more common after WWII.
Do you have the schematic/service information for this radio? If not, you need to contact Chuck Schwark and get yourself a really good quality copy.
http://www.philcorepairbench.com/schematics.htm
As for the field coil, you can sub an 800 ohm resistor, and increase the value of the filters somewhat. Like increasing (88) from 16 to 22 or 33 uF. I think 47 uF will be sufficient for (13C) even with a resistor in place of the original field. Use a resistor rated at 25 watts minimum. This resistor will run hot!
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Ron Ramirez
Ferdinand IN
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Thanks Ron - you've addressed a ton of my concerns with this radio  . I do have a fairly decent copy of the schematic - but no parts list. I did look a little closer at e-cap 88. It looks to be original and there are 3 terminals - 2 of which appear to have continuity (rather than a short). Perhaps this is solely for convenience to allow for ease in wiring - though I've never seen this before .
Again, thanks - as I progress in reviving this radio, I'm sure I'll have other questions. Great resource here!!!
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FWIW, my info packets include parts listing, alignment instructions, production changes (if issued)
and much more from the original 1941 Service Bulletin and ancillary Philco documentation.
Chuck
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Update.... I had a new 10" PM speaker and an appropriate power resistor to use - but browsing Ebay recently, I found the actual speaker. The seller had listed some assorted radio parts from an estate - some of which were the dial scales from a Tropic. He also had a 10" speaker listed as "unknown" - so I had him check the voice and field coil - which were spot-on for this radio. I'll start recapping soon - but at least I won't have to worry about the speaker work-around now.
However - the grill cloth was a bit tattered and dirty. I tried gently hand washing it - big mistake!!! Even using cold water, it shrunk up just enough to be unusable. Radio Daze used to carry a reasonable-looking replacement (pattern #69) - but they no longer do. Does anyone have a spare bit they'd like to sell - or do you know of someone who does??? It would need to be about 12" wide and 16" in length. Any direction would be greatly appreciated......
JG Jackson
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Congratulations on finding the speaker. I missed that (I would not have bid on it anyway since my 41-788 is complete and my 42-788 has its original speaker also), but I think I bought the knobs from the same seller - I put them on my 42-788. I've seen the dial scales on eBay more than once, I guess the seller kept relisting them.
I recall junking either a 42-1008 or 46-1209, and the cloth was identical to the 41-788 cloth. I don't have any more; I used it in another project. You might consider this if you can find a junker 1942 or 46 Philco console.
I recently bought some #71 cloth from Radio Daze to put in my 41-758 Tropic. The #72 might have been a better choice. Pattern 71 has been discontinued now, as has 72, but Radio Grille Cloth Headquarters is still advertising "limited supply" on these.
http://www.grillecloth.com/pages/limited.php
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Ron Ramirez
Ferdinand IN
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Thanks Ron..... I'll have to keep an eye out... Hope all is well and that you're mended completely....
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So far, so good; thanks. 
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Ron Ramirez
Ferdinand IN
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Just looked at my 41-290..... hidden behind the vertical cabinet bars, it has about a yard of that exact grill cloth running vertically.... Unfortunately (fortunately?), that console is in much too good an original condition to be a donor.....
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I saw your post on this same subject over at the Temporary Alternative Forum.
I notice Dave Doughty posted a picture of his 42-788. He gave me permission previously to show his set in my site's Gallery. Anyway, I noticed that the cloth in the photo he posted in your ARF thread shows up better there - and looks just like the discontinued Pattern 72 from Radio Grille Cloth Headquarters. A different pattern than what is on my 41-788 (and what was on your 41-788).
I just sent John Okolowicz an email to see if he still has any Pattern #72 left. I'll let you know what he says. My 42-788 needs cloth; if he has any, I'm going to get some.
Unlike my 41-788, which is in nearly excellent condition but unrestored electronically, my 42-788 needs total cabinet and electronic restoration. It has incorrect cloth and needs quite a bit of veneer repair. Fortunately, it's all there including the speaker. It did not have any knobs when I bought it, but has a complete set now as I mentioned earlier.
As for the cloth you seek, you never know, sometimes a junker can yield good cloth. I don't know where you are located, but if you are anywhere near the Kutztown, PA, Lansing, MI or Willowbrook, IL meets, you might find a junk console at one of those meets before it is put in the dumpster (on in the bonfire at Kutztown). Just a thought.
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Ron Ramirez
Ferdinand IN
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JG - I am buying the last piece of #72 cloth that John has. If you want any, LMK and I will be able to furnish enough for your project at a reasonable price.
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Ron Ramirez
Ferdinand IN
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Joann's - a crafts and fabric store - is having their "Midnight Madness" sale this week and I went there half-heartedly looking for a substitute. I did find a tolerable match - not too obvious to most eyes - in the upholstery section. $25 a yard.... I got a half yard + 50% discount sale - about $6.50 for enough to do about every 41-788 on the phorum. I'll post some pix when it's done....
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I'm about 3/4 of the way into recapping.... there are 4 big black Philco caps - .006MFD @400V - they look a bit more substantial than the others in the set and I'm not absolutely sure I've run into these before.... Are these anything special??? Can I replace with garden variety mylar caps of the same value???? Thanks...
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About the caps, mylars ought to do fine. Just keep the lead dress the same. If you can't get .006, .005 or .0056 should be OK. 400 or 600 volt types are both OK. I usually just keep 600 volt types around to simplify matters.
Onw word of caution about the "grille cloth." Upholstery material may not be be acoustically transparent enough, thus might muffle the sound which sould either cause the bass notes to become damped, and/or absorb the higher pitches. You can check this out by putting some on a working radio and see if this is happening. Get a kid to do the test, if your hearing is as bad as mine. If the material fails the test, you could always make a pillow.
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