The PHILCO Phorum
Philco 620 - Printable Version

+- The PHILCO Phorum (https://philcoradio.com/phorum)
+-- Forum: Philco Radio Discussions (https://philcoradio.com/phorum/forumdisplay.php?fid=5)
+--- Forum: Philco Electronic Restoration (https://philcoradio.com/phorum/forumdisplay.php?fid=8)
+--- Thread: Philco 620 (/showthread.php?tid=21313)

Pages: 1 2

Philco 620 - Neo6425 - 05-11-2020

Hello folks!
I just purchased a Philco 620 and I'm about to attempt my first restoration.
[Image: http://www.ispdi.com/Philco/images/Front.JPEG]
Although I'm a newbie I'm pretty sure it's a Philco 620 based on the label inside the cabinet that matchs up with the tubes in the chasis.
[Image: http://www.ispdi.com/Philco/images/Label.JPEG]
Here's the chasis:
[Image: http://www.ispdi.com/Philco/images/Chasis.JPEG]
Here's another pic of the chasis with the Dial:
[Image: http://www.ispdi.com/Philco/images/Dial.JPEG]
And here here are some pics after I used some compressed air to remove the funk of 10,00 years that was left behind.
[Image: http://www.ispdi.com/Philco/images/Chasis1.JPEG]
Here are some pics of the bottom of the chasis:
[Image: http://www.ispdi.com/Philco/images/BottomChasis.JPEG]
Here's another shot:
[Image: http://www.ispdi.com/Philco/images/BottomChasis1.JPEG]
After cleaning it up a bit, I took a chance and connected it to my Lab-Volt that allows me to slowly bring up the voltage. Here's my Lab-Volt:
[Image: http://www.ispdi.com/Philco/images/Lab-Volt.JPEG]
I slowly turned up the voltage and the only thing that worked was the lamp light for the dial - the tubes did not fire up, no hum, no static no sound at all.
So now my next step is to replace all the caps. Question: some vendors offer offer pre-packaged sets of caps for pre WWII radios. Should I go this route or should I use the parts list I found for the 620 and purchase them individually? Again, this is my first restoration so any advice is gladly accepted.

RE: Philco 620 - morzh - 05-11-2020

OK,

First things first.

Bringing this radio up was not the best idea, next time don't.
Before you recap, that is.
If you want to check the transformer, take out all tubes, especially the rectifier tube and measure the outputs at there rectifier socket, between the fat pi s (5V) and thin pins (600 plus volts).
This will tell you if the transformer is good, as if it is not you might re-adjust the strategy.

Now, the radio was repaired, as there are tubular caps placed instead of the backelites; if they were smart they would use the latters as solder posts, if not, then they paralleled them.

The radio seems clean. Even the speaker cord, which in 620 is soldered in, is not cracked.
Desolder it first and label, or it will hinder the chassis being handled.

Resist the urges to straighten and beautify the inside wiring: you will end up with hum you won't know the reason of.
If replacing a wire, make sure you run the new one exactly the same way.

Also, finish restoring before buying all those letters etc. See if you want spending money on this particular radio once it is done.

RE: Philco 620 - Neo6425 - 05-11-2020

Thanks morzh! 
Yeah, I couldn't help myself, the temptation was too strong not to fire it up. 
Your advice is greatly appreciated and I will follow it. 
Thanks again!

RE: Philco 620 - rfeenstra - 05-11-2020

Congrats on your radio! Whether you use pre or post WWII values is of little consequence. I tend to like the pre WWII. If you are planning on more restorations, you probably would like the kit. It's nice to have the whole selection available as you get into the restoration of various radios. I have done that and then when I run low, just order the ones I need. You might also consider the resistor kits as the "dog bone" resistors are often way out of tolerance. I usually use a 1 or 2 watt replacement. The physical size of modern resistors is much smaller than the original 1/2 watt dog bones so the 1 or 2 watt resistors are not a size problem and give plenty of heat capacity. I special order the higher wattages that are sometime necessary. It looks like you have 1 dog bone that is 5 watts or so. A 10 watt would fit nicely if that resistor is out of spec. I just put in an order at Just Radios for caps and resistors! I've also ordered from Mark Oppat's Old Radio Parts. He has post WWII values at, I believe, a lower price than Just Radios.

RE: Philco 620 - Neo6425 - 05-11-2020

rfeenstra, 
I’m in the process of researching capacitors now, so I appreciate your opinion. I may just go real slow, follow the schematic and create my own list of what I need. It also forces me to become a bit more familiar with the radio.
I’m also discovering that reading these older schematics is trickier than I thought. 
Thanks!

RE: Philco 620 - morzh - 05-11-2020

Reading the old sch is no trickier than a ything of today's, except the tubes symbols that are no longer used as uch, the rest is the same.
They do have mistakes in Riders, so if rewiring, redo the existing wiring by snip-replace, as if you try to trace it using the sch you might make their mistakes.

I highly recommend finding the late Ray Bintliff's book about the Philco caps. I cannot overstate it usefulness and am only remorseful for not buying it 7 years earlier.
Meantime, some info about backelite block caps and other parts can be found at Philco Repair Bench of Chuck Schwark.

RE: Philco 620 - Neo6425 - 05-11-2020

Morzh,
I’m having a though time finding the book you recommended - Philco Condensers and More, 4th Edition. It is no longer available on Amazon or the book resellers I use.  Antique Electronic Supply had it but is no longer selling it either.
I’d really like to read it, especially after hearing what you said in your post.
Please let me know if there’s anywhere else to look to find a copy.

Also, as I was searching for the book you recommended, I found the obit of Ray Bintliff - what a truly amazing person and what a legacy. 
Thanks for sharing!

RE: Philco 620 - morzh - 05-11-2020

https://www.amazon.com/HiMedia-GRM1047-500G-Ammonium-Dichromate-Extra/dp/B00DYO84IO

Here's the 2nd edition.

I got my from Ray himself shortly before he died. Glad I did.


Here is Chuck's website, he has most of them too.

https://www.philcorepairbench.com/bakelite-block-condensers/



PS. Just found this website. Dunno if legit. Think it is. Selling 4th edition.
The phone is alive, call themm first thing tomorrow. They are 516 code, Port Washington NY so not far.
Check it out.

http://www.antiqueradio4.com/Merchant2/merchant.mvc?Screen=PROD&Store_Code=AM&Product_Code=PCAM&Category_Code=BL

RE: Philco 620 - Neo6425 - 05-13-2020

Quote:morzh wrote:
If you want to check the transformer, take out all tubes, especially the rectifier tube and measure the outputs at there rectifier socket, between the fat pins (5V) and thin pins (600 plus volts).

This will tell you if the transformer is good, as if it is not you might re-adjust the strategy.

I took your advice morzh and I measured the output at the rectifier socket. I had 5V between the "fat pins"
[Image: http://ispdi.com/Philco/images/Rectifier5v.jpg]

and I had 600 plus volts between the "thin pins".
[Image: http://ispdi.com/Philco/images/R600v.jpg]
Based on this it seems the transformer is good.
Thanks for the help!!

RE: Philco 620 - radiorich - 05-14-2020

Hello Neo6425,
Nice radio and Because we would not want see you cause the power transformer to burn up that is why Morzh not to plug it in .
Glad to see your voltages are good coming out the power transformer . then on those little blocks with the screw going thought it and wires attached at the bakelite blocks and once you find the right value parts . you are very lucky that chassis looks really good .
it's best to find chassis that not hacked that looks original .
Sincerely Rich
P.S. you come to the right place far as help morzh and Ron are great Ron has written books on Philco

RE: Philco 620 - Neo6425 - 05-14-2020

Quote:Morph wrote:

"The radio seems clean. Even the speaker cord, which in 620 is soldered in, is not cracked. Desolder it first and label, or it will hinder the chassis being handled."
The speaker is desoldered and this leads me to a question that will prove how little I know: This speaker has three wires on it and it looks completely different from some of the antique speakers that I've seen. I'd like to bench test this speaker. How would I go about doing that?

RE: Philco 620 - morzh - 05-14-2020

All you need to know is if your field coil and transformer primary are ok.
This is done with an ohmmeter.
If the speaker is clean and not ripped, provided the primary and the field are ok, there is little chance it won't work well. I never test anything more than that. They are 400 ohm and 1140 ohm respectively (value could be within reasonable proximity).

RE: Philco 620 - radiorich - 05-14-2020

Helllo morzh,
I think Neo6425 found a good radio the chassis looks in good shape

RE: Philco 620 - morzh - 05-14-2020

Rich,

Wholeheartedly agree, this is exactly what I said in my post #2. Very clean hassis.

RE: Philco 620 - GarySP - 05-14-2020

Welcome Neo6425! I have to tip my hat to you! That is one tight chassis to be attacking as a "first restoration". When you get through that one you should have no problem with most any other radio. You have a good bunch of guys here ready to offer any advice you may need. Take care, and BE HEALTHY! Gary