Posts: 2,118
Threads: 112
Joined: Jun 2010
City: Medford OR (OR what?)
Yep, I used NP 630V caps in mine. They cost a lot more than electrolytics, but at 1.5mf, they are still cheap. Big ones over 10mf are $6 or $7 each.
http://philcoradio.com/phorum/showthread.php?tid=6731
Posts: 15
Threads: 2
Joined: May 2013
City: United States
These sets also use "bakelite block" caps, too.
Posts: 2,118
Threads: 112
Joined: Jun 2010
City: Medford OR (OR what?)
Yes, and there are 2 other metal cans besides the big one.
Posts: 15,704
Threads: 551
Joined: Oct 2011
City: Jackson, NJ
Yes, but they are a snap to restuff: they are not potted inside. You open them by straightening the tabs and the cap pulls out readily.
Posts: 15
Threads: 2
Joined: May 2013
City: United States
The same type of cap can be used in those as well?
Posts: 2,118
Threads: 112
Joined: Jun 2010
City: Medford OR (OR what?)
Well, yes, 630 Volt non-polarized of the correct value.
Keep in mind that, as I said in the thread above, most of the resistors are going to be bad as well. With the type used in that radio, they don't just drift off, they go open.
(This post was last modified: 05-27-2013, 08:38 AM by Phlogiston.)
Posts: 15,704
Threads: 551
Joined: Oct 2011
City: Jackson, NJ
Pete
For these purposes any type of cap can be used. At these frequencies the caps behave very close to ideal cap and the currents are small.
Say, in today's digital devices or in a switching power block there's no way you could take an electrolytic cap, solder it to wires 6" long and be siccessful. In the old radios this is OK to do.
So as long as your cap meets the voltage/capacitance requirements it is OK to use.
In case of electrolytics you have to watch your polarity.
One notable exception is RF filter caps; they need to have a very good thermal drift coefficient and need to be soldered using short leads. This is why mica caps were used there; today you can use either those or NPO/C0G dielectric type ceramics.
For all your other major needs (sorry for the pun) except where the electrolhytics use is warranted due to high capacitance (there is no other reason to use them) polyester film caps will do just fine.
Posts: 1,958
Threads: 146
Joined: Jan 2013
City: Westland, MI
I used polyfilm caps for everything. The bakelite bypass caps aren't very hard to rebuild, just be gentle with them so you don't break them. Lots of info in the website on how to restuff them. One has resistor wire in it as well. I used a 250 ohm half-watt resistor there. Take care. Gary
"Don't pity the dead, pity the living, above all, those living without love."
Professor Albus Dumbledore
Gary - Westland Michigan
Posts: 15,704
Threads: 551
Joined: Oct 2011
City: Jackson, NJ
Rebuilding a backelite takes me some 10-15 minutes, and I am taking my sweet time; rebuillding an electrolytic takes me a minimum of 1hr. You have to desolder it, cut part of it off, gut it, clean it, fit the new caps in, possibly drill some holes, pot it, glue it back together, solder it back.
A backelite - just unscrew it, no desoldering, gently heat it,, push the guts out, put the new cap in, solder it, screw it back. A snap.
Posts: 15
Threads: 2
Joined: May 2013
City: United States
Will mylar caps work as good as poly film?
Posts: 7,283
Threads: 268
Joined: Dec 2009
City: Roslyn Pa
Posts: 5,074
Threads: 269
Joined: Nov 2012
City: Bandon
State, Province, Country: OR
Morzh, why do you pot the restuffed condenser can? I've cut the can, gutted it, drilled the holes for cap leads and then used a thin strip of electrical tape to hold the two parts of the can together before clamping the can into the mounting bracket. That seems to hold things pretty well, the tape is not visible since its under the clamp and I can easily undo it all if the cap should need replacing or, heaven forbid, I screwed up the restuffing in the first place. what am I missing here? Thanks!
Posts: 15,704
Threads: 551
Joined: Oct 2011
City: Jackson, NJ
No reason other than it will old a cap on its thin leads from sagging and shorting to something. If the leads are short and stubby and he cap is small ... no real need.
Just something I am mentally comfortable with.
Posts: 5,074
Threads: 269
Joined: Nov 2012
City: Bandon
State, Province, Country: OR
Ah..thanks, hadn't thought about sagging although I do insulate the leads.
Posts: 15
Threads: 2
Joined: May 2013
City: United States
When I had the chassis out of the cabinet today, I noticed some past repairman bridged an electrolytic across one of the ones on that large can. I don't recall seeing that electrolytic on the schematic. Next time I have it out, I'll take a pic and post it on here.
Users browsing this thread: 2 Guest(s)
|
Recent Posts
|
Philco 91 Speaker Replacement
|
The spider is glued on the cone and so is the voice coil. I think you can use a cotton swab dipped in acetone and carefu...RodB — 02:42 PM |
Restoring Philco 37-604C
|
Yes I saw that. If I knew, I'd probably try to arrange for getting it myself. But I have just got one.
Which does not m...morzh — 01:44 PM |
Philco 38-2 Automatic Tuning
|
When you push the lever, you are supposed to rotate the disk to the desired station.
Then the magnetic tuning will acqu...morzh — 01:42 PM |
Philco 38-2 Automatic Tuning
|
I figure out the muting from another picture that helped. Now I need to know how the automatic tuning works. When I push...dconant — 12:11 PM |
Philco 91 Speaker Replacement
|
How would I go about removing the spider from the cone?dconant — 12:04 PM |
Philco 38-2 Automatic Tuning
|
Hello, I am having trouble getting my automatic tuning to stay unmuted. If I play with the tuning handle I can get it to...dconant — 10:51 AM |
Does anyone make photofinish replacements?
|
Here’s the link to the DIY photofinish section of our site:
klondike98 — 09:46 AM |
Delco car radio Peko vibrator converstion issues
|
Hi Richard,
Thx for posting the schematic. As I remember as a kid, these were great performers for the time, likely...MrFixr55 — 08:56 AM |
Delco car radio Peko vibrator converstion issues
|
hello mr Fixr,
The Electro Powersupply that I am powering the radio with has a huge choke plus a 10,000ufd electrolyti...radiorich — 10:58 PM |
Delco car radio Peko vibrator converstion issues
|
How about putting a choke in the power supply?
The big cap was likely an attempt to stabilize the DC. Kids who cre...MrFixr55 — 09:19 PM |
Who's Online
|
There are currently 1798 online users. [Complete List] » 1 Member(s) | 1797 Guest(s)
|
|
|
|