05-10-2023, 12:14 PM
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.
[Image: https://www.dropbox.com/s/sos00d52xk49ph....JPG?raw=1]
[Image: https://www.dropbox.com/s/wnacr0g2ktcxcl....JPG?raw=1]
[Image: https://www.dropbox.com/s/5bykhtxi3dwrk1....JPG?raw=1]
[Image: https://www.dropbox.com/s/wp9xvbjk3fkm8c....JPG?raw=1]
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.
[Image: https://www.dropbox.com/s/cumzt0z4uwy832....JPG?raw=1]
[Image: https://www.dropbox.com/s/yt1yr4illvdlac....JPG?raw=1]
[Image: https://www.dropbox.com/s/3p2oqe2omypub5....JPG?raw=1]
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...
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.
[Image: https://www.dropbox.com/s/sos00d52xk49ph....JPG?raw=1]
[Image: https://www.dropbox.com/s/wnacr0g2ktcxcl....JPG?raw=1]
[Image: https://www.dropbox.com/s/5bykhtxi3dwrk1....JPG?raw=1]
[Image: https://www.dropbox.com/s/wp9xvbjk3fkm8c....JPG?raw=1]
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.
[Image: https://www.dropbox.com/s/cumzt0z4uwy832....JPG?raw=1]
[Image: https://www.dropbox.com/s/yt1yr4illvdlac....JPG?raw=1]
[Image: https://www.dropbox.com/s/3p2oqe2omypub5....JPG?raw=1]
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...
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.
