Electrolytic Cap on Model 650 question
Posts: 26
Threads: 9
Joined: Nov 2020
City: Ottawa
State, Province, Country: Ontario
https://philcoradio.com/library/download...l.%201.pdf
Working on changing the caps on this Model 650 and was wondering what voltage is required for Part #71, the 1, 2, and 3 mfd electrolytic. As well is is ok to just use a non polarized film cap here. I have those on hand but would have to order the electrolytic caps. Thanks.
Posts: 1,402
Threads: 70
Joined: Oct 2007
City: Linn Creek, MO
Bob, I would definitely use film caps, they will practically last forever, not so for electrolytics.
Steve
M R Radios C M Tubes
Posts: 15,704
Threads: 551
Joined: Oct 2011
City: Jackson, NJ
The #71 cap's values, as long as they meet the sch values, are OK. You could use 10uF all around if you have this cap available already and do not want to buy more caps. 450V is my minimum voltage, 500V is preferred.
Yes you could use film caps, as Steve has already said.
The only cap you might want to have as close as possible to the value is the #78 an 8uF one.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
Posts: 26
Threads: 9
Joined: Nov 2020
City: Ottawa
State, Province, Country: Ontario
Thanks gentlemen. I appreciate your knowledge and assistance.
Posts: 1,583
Threads: 99
Joined: May 2008
City: Omak
State, Province, Country: WA
Hello bob,
Film caps are good choice because I need to replace the filter capacitors in my Philco 610b that restored about 20 years ago anyway this time I am using Film capacitors !
Sincerely Richard
Posts: 15,704
Threads: 551
Joined: Oct 2011
City: Jackson, NJ
I have always advocated the view that electrolytic caps are being badmouthed unfairly.
Yes, if using GP caps, which are higher impedance and not high ripple current-rated, they will go dry eventually. Not all, in fact, but mostly those in the very first rectifier filter position.
These caps experience high peak ripple and some significant RMS ripple, which, along with voltage/temperature eventually lead to their deterioration.
However, properly sized electrocyltic caps will last if not forever, then at least many, many tens of years. And typically they are cheaper than comparable good quality film caps.
I use Panasonic high ripple-low impedance 105C-rated caps. They are about $1 apiece in qty of 10+.
Another key is, of course, regular usage. Caps that do not get usage behave same as those in long storage and need re-forming due to developing thinning dielectric layer which is maintained when the cap experienced voltage across it.
This said, it is a matter of taste. I have a generous supply 22uF 450V caps from Panasonic, and I use them most everywhere in the rectifier filters. If I need 10uF, I serialize two 22uF.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
Posts: 1,583
Threads: 99
Joined: May 2008
City: Omak
State, Province, Country: WA
Hello Guys,
my go to years ago were sprague atoms now I use nichicon !
Posts: 15,704
Threads: 551
Joined: Oct 2011
City: Jackson, NJ
Any Japanese company will make good caps. Nichicon, Chemi-con, Rubicon, Panasonic.
I was searching for the highest ripple rating at 120 Hz, and found Panasonic to ve the highest, but of course there will be close matches or even better ones, undiscovered by me.
Just do not use no-names, or Lelon, or.....
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
Users browsing this thread: 1 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 1244 online users. [Complete List]
» 1 Member(s) | 1243 Guest(s)
|
|
|
|
 
|
![[-]](https://philcoradio.com/phorum/images/bootbb/collapse.png "[-]")
