[WyTex]

Howdy Buzz -

I'm restoring a 29' model 87 Lowboy and about to tackle the condenser bank myself. Would radial caps be a better fit than axial for this circuit?

Thanks,
Paul

[morzh]

Paul

Having done the same, the axias are better - easier to mount and create busses when needed.

[WyTex]

Thank you.

[Buzz]

1929 Philco Model 86 Restore on Youtube
Part 7 now uploaded
https://www.youtube.com/watch?v=P7wK4-YDRCY

[sam]

buzz

great vids funny as H**l keep them coming

[Buzz]

1929 Philco Model 86 Restore on Youtube
Part 8 now uploaded if interested
Buzz

https://www.youtube.com/watch?v=LgcaleMKk8g

[Radioroslyn]

Hey Paul
I repaired a model 87 a year or so ago. Did chronicle the work here on the Phorum. You can do a search to find it. One of my favorites of the early sets.Definitely use mylars in the power supply, I didn't and the input cap is shorted after abt 6 months of use (3hrs a day or so).
GL
Terry N3GTE

[WyTex]

Hi Terry -

Thanks for the tip! I placed the cap order last week but did not order Mylars. I'll put in another order. Really appreciate the advice.

Regards,
Paul

[morzh]

111 is not unlike those, I also used films in the power filter. After all why use electrolytics where they were not before and the capacitance needed is 2uF tops.

[jerryhawthorne]

I[m a great believer on the solen fast caps for low mfd power supply caps in radios. Tried e-caps in a Scott and blew out after 7 hours of running. Tried a new set with the cap cover off (stuffed) and an hour they were getting very warm. The Solen cap in there, cool. Same experience as Terry, different radio.
Best, Jerry

PS: Mike, I used them in my 111 and 112 as well!

[morzh]

Jerry,

I remember, you posted the photos in my thread.

As for the ecaps, when used in large pserul radios, one needs really to pay attention to the ripple ratings. I is not a cap's fault it is used under conditios outside the specifications.
And, unfortunately, ecaps of small capcitance also have small rippe current rating, a 20uF cap going possibly to 200-300 mA, which means that one needs to patallel-serialize them to meet the requirements. Good rule of thumb is, need an amp, rate an amp (very conservative folks go 5-fold). For continuous operation in enclosed space I would also rate at least 2-3 times the load.

But those caps sold by hobbyists websites are GP caps, not even high-ripple which you need several.

Yes a film cap is better, though I could never find their ripple specs.

[jerryhawthorne]

Mike, you are correct, there are other things than voltage rating and mfd values that come into play. I like many people who are not a tune to things like ripple and current, learned the hard way. Easy to say a 2mfd cap at 500V on the schematic and find an e-cap will not last, with some neat disaster happening. Thank heaven the scott had a fuse. I'm certain poly caps will work fine, I like the solen fast caps as higher quality than the polys.
Best, Jerry

[Buzz]

1929 Philco Model 86 Restore on Youtube

Part 9 now uploaded if interested
Buzz

https://www.youtube.com/watch?v=KMCM-McSfgE

[Buzz]

1929 Philco Model 86 Restore on Youtube

Part 10 now uploaded if interested
Buzz

https://www.youtube.com/watch?v=aUkoNQYdh7o

[Buzz]

1929 Philco Model 86 Restore Part 11
now uploaded, if anybody is interested.

https://www.youtube.com/watch?v=Cn5ekGqZ8Bc