The PHILCO Phorum

Full Version: Howard 256 restoration
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The Howard 256 restoration has begun. The schematic can be found at THIS LINK. Its the version with 2 to 6.5 mcycles shortwave band seen on page 8-10 at the top.
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The original dual 8/4 mF electrolytic had been clipped off and a set of Mallory 8mF caps had been placed under the chassis. Fortunately they left the original cardboard can in the set and I was able to soften the tar and get the guts out with a combination of heat gun, box cutter blade, screw driver, a long screw into the cap and pulling with pliers and swearing. The new caps are inplace and ready to be wired in.

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This one is going to have some interesting work around the dial. Its a construction I have not seen before, but that's for later. Do the easy part first... Icon_lol I won't be cleaning up the chassis to look shiny new but there was a lot of dirt, dust and some rust that will come off. So far I think all the coils and transformers are intact. The band switch has something wrong with it. There are only two bands but the switch rotates more than two stops so I think there may be some damage there. Looks like someone did some soldering onto the shaft near the body of the switch. At least is still rotates. More later.
Hello bob,
Yes, the old long screw trick i thought I was the only one to do that !!
I like using those cheap gold tone screws for stuff like that .

Sincerely Richard
hello Bob,
I for got to ask how do you like that repair stand ?

Sincerely Richard
The stand works great. Has helped me on a number or restores now. I once made a stand for a 48-482 I was working on, it was a big contraption. Not sure this stand would handle a 48-482 but it might. Certainly is good for the normal sized table chassis. It’s made by Phorum member Simon Wa3uay.

Here's that homemade stand. I have to add that the design was based on something I had seen somewhere in a forum but don't recall where. It was useful but overly large for the space I had so I dismantled it.
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Hello Bob,
Yes, I too bought that same stand it is very handy I will be using it here next month when I am off for summer break my Philco 610b needs some new electrolytic filter capacitors one went bad after almost 20 years of use .

Sincerely Richard
Just a little progress today. Finished up the electrolytic cap connections and stuffed three of the paper caps in this section of the radio. One was a replacement of a replacement so I had to find a reasonable looking paper cap in my pile of old caps. It looks a lot cleaner with the old electrolytics that were tapped in under the chassis (the new power cord will need to go back in after all else is done).

Before:
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After:
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I finished recapping the radio and found that it is indeed working. A little aligning and I can pull in the one AM station that is local with a 30' antenna and my SSTran broadcast is solid. Interestingly, the band switch which has 3 positions for two bands does work. Left is SW, center is dead and right is BC. I don't know if they designed it that way or it was a replacement switch at some point.

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The dial was a little different than others I've seen. Its a curved glass cover over a flat plastic dial face with a rubber gasket around the glass dial. The plastic dial face fits against the rubber gasket. Of course the old rubber was toast and fortunately I had a new strip of gasket in the parts drawer I could use.

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Now its on to the cabinet...
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Real nice work, Bob! Take care and BE HEALTHY! Gary
klondike98 Wrote:I don't know if they designed it that way or it was a replacement switch at some point.

I can't see Howard spending money on a more expensive switch than the 4PDT shown in the print.
Thx Gary

Dale,Yes, I think you are right it’s a replacement.
I finished up the Howard 256 today. After getting the cabinet glued back together it got a very light sanding, two coats of sanding sealer followed by another light sanding, van dyke brown ultra classic on the trim and a very light medium brown walnut on the entire cabinet. The black around the dial was just an acrylic black paint. Five or six coats of gloss lacquer, rub out with rottenstone and wax with Howard's Wax & Feed. The top did not need grain filler so I elected not to use any although the front and sides could probably have used some. I don't think the center band switch knob is the correct one but I could not find one so went with one that was similar in design to the volume and tuning (i.e. one of the generic radio knobs from Renovated Radios.)

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Hello Bob,
Wow that is one sharp looking radio !!

Sincerely Richard
Hello bob,
yes, I too love my SStran and what I found really made mine sing is when i put in a grounding rod just for the transmitter .

Sincerely Richard
Nice work kid! Paul B
Sharp looking radio Bob and came out great! Icon_thumbup

Ron
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