EH Scott Radio Enthusiasts

The Fine Things are Always Hand Made

The 4.7uf multi cap was removed from my Philharmonic some time ago, and as I would like to have it looking a little more authentic under the chassis this left me two options,

find a donor chassis, in the UK that is nearly impossible, the other way is to make a box from scratch,

here is a photo showing the wrong cap, bottom left in the picture,as the wires have been cut and were too short to be of use I came up with this answer,

Yup that's right, shoe laces, this brand is unwaxed cotton, as the original colors have faded, they are a near perfect match, both in color and weave. although there a limited color range available.

First cut the end from the lace and tease out the cotton inner,

after pulling these from the shoe lace, this leaves a braid,

the next step was to make a tin box, thanks to Scott Seickel for a couple of excellent photo's

here is my box, made from an old 1/2 gallon can, ready for stuffing,

I used four 4.7uf 600v polypropylene caps, there is plenty of room in the box for these,

the artwork is made with heat transferred laser print,

finally the completed cap with shoelace covers on the modern wires.

The only problem is I can't replicate the rust and 80 years of age,

Mike

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Very nice Mike.  The later Philharmonic chassis did use the FP can for this application.

Norman

Thanks for the reply Norman,

my Philharmonic is an early west coast pointer dial,

the cap someone fitted in the past was four x 20uf, not the 4.7uf that should be there, the white wire is Ptfe by the slippery feel,

the 5k dropper is missing as well, I have a ohmite resistor from Mouser for the job

Mike

Just stick it out in the U.K. rain for a few weeks...that should do it.

Hello,

Looking for the can that holds the 4.7mfd capacitors in an early Philharmonic. I see that other folks have made appropriate boxes, but I just dont have the tools to make one. 

Any leads on a original box or other advice would be welcome.

John

Here are the drawings I made of the boxes, they are different in the way they are put together, the metal can be cut with scissors (just don't get caught by the wife).

the metal is already tinned and solders like a charm,

I used a steel rule and a block of wood to fold the boxes.

And the second box,

I think it's the first drawing that you want, make the box first and solder the bottom on after.

Mike

Mike - very cool.

A very early Pointer Philly I have - has the soldered 4 unit box stamped with  4 x 4 MFD @ 300 volts.

A somewhat later Pointer Philly I have has the more modern cylindrical 4 unit filter like in Mike's at 4 x 5 MFD.

The much later BOL Philly from 1940 still uses the more modern cylindrical 4 unit. at 4 x 5 MFD.

Rebuilding with four  modern 4.7  MFD at 450 volts caps is fine.

*

All three Philly's use the soldered box containing 7 caps at .1 MFD which I rebuild with 630 volt film caps.

Thanks, Mike!

Cheers

mike hadley said:

Here are the drawings I made of the boxes, they are different in the way they are put together, the metal can be cut with scissors (just don't get caught by the wife).

the metal is already tinned and solders like a charm,

I used a steel rule and a block of wood to fold the boxes.

And the second box,

I think it's the first drawing that you want, make the box first and solder the bottom on after.

Mike

Hi David,

Would this be 7 X 0.5 mfd?

All three Philly's  use the soldered box containing 7 caps at .1 MFD which I rebuild with 630 volt film caps.



David C. Poland said:

Mike - very cool.

A very early Pointer Philly I have - has the soldered 4 unit box stamped with  4 x 4 MFD @ 300 volts.

A somewhat later Pointer Philly I have has the more modern cylindrical 4 unit filter like in Mike's at 4 x 5 MFD.

The much later BOL Philly from 1940 still uses the more modern cylindrical 4 unit. at 4 x 5 MFD.

Rebuilding with four  modern 4.7  MFD at 450 volts caps is fine.

*

All three Philly's use the soldered box containing 7 caps at .1 MFD which I rebuild with 630 volt film caps.

John, this is the other box I made for my radio, it does contain 7 caps at 0.5mfd, it's made and lined with transformer paper,

the caps soldered to the metal box,

The caps are then put inside the other half of the box with the wires passing through the hole in the side,

Then the side is soldered in place, this photo shows the two boxes before installing in the radio, note they are made differently  

The 4.7uf box is not only folded differently the leads come out of one end.

if you can't get transformer paper you could use heavy weight acid free paper, polyester film would also do.

Mike

Philly specs info for the box with 7 cap metal box are .05 MFD each  - see part #74 on Riders page 14-60.

I use 630 volt film caps. I just cut the old wires a couple inches from the box and use new short orange leads exiting the rebuilt box, and then solder to the old leads and slide heat shrink over the solder connections.

*

The 4 unit filter cap is 4 MFD each at 300 volts per part 112 on Riders 14-60 , but a later Pointer and even later 1940 BOL, actual filter is 5 MFD each section .

Is that seven 0.05mfd or seven 0.5mfd ?

It is 7x 0.5 as noted earlier. I think Dave got an extra 0 in there. I'm in the process of rebuilding one of these myself. Years ago, a fellow here in Ohio was making replacement units. I suspect there would be interest in these again if someone has the time and resources.

Kent

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