Thread Rating:
  • 1 Vote(s) - 5 Average
  • 1
  • 2
  • 3
  • 4
  • 5

60 MB restoration
#31

Not yet, but I will and you'll see I ran into a number of problems.

One, the output attenuator isn't working on my 3336A. Luckily, it's stuck on a level that was OK for this project, but I'm going to have to do something about it.

Two, the z-axis input on my HP 54600B scope only does trace blanking - not intensity modulation. So I had to dust off my old 465 scope.

I'm also a little disappointed that the 3336A doesn't support FM modulation, but the AM modulation does work very well.
#32

Spent tonight repairing a pair of speakers.

Here's the one that came with the 60MB. It had been re-coned ages ago and the glue failed on both he surround and spider. It still sounded OK until the volume was really cranked up when it would started buzzing badly. I spread some Aleene's clear gel tacky glue around and will let it set up over night.
[Image: http://farm8.staticflickr.com/7396/10568...7298_c.jpg]

[Image: http://farm4.staticflickr.com/3700/10568...ff17_c.jpg]

I also tackled the speaker that came with the parts chassis. The cone was completely trashed and the spider damaged but useable I think.
[Image: http://farm4.staticflickr.com/3831/10568...78fc_c.jpg]

I cleaned off the glue residue with Acetone and used a little Naval jelly on the frame. Some Boeshield T-9 should keep the rust at bay.
[Image: http://farm3.staticflickr.com/2876/10568...c8c6_c.jpg]

The new cone came from MAT Electronics. I just had to trim about 1/16" around the rim and slightly enlarge the VC hole. The foam surround does stick up a bit beyond the frame edge so I'll probably have to use some shims
[Image: http://farm8.staticflickr.com/7383/10568...900a_c.jpg]

I'll fire them up again tomorrow and use whichever sounds better in this set.
[Image: http://farm6.staticflickr.com/5532/10568...c744_c.jpg]
#33

Although my re-coned speaker works OK, at higher volume levels that damaged old spider starts to vibrate. The other speaker is working great now that the surround and spider have been glued back down so that's what I'll stick with.

Tonight I moved on to wiring in a reproduction cloth covered power cord. I'd heard about the "Underwriter's Knot" before, but this is the first time I've used it. It's easy to tie and really does provide a great strain relief. I also added a bit of heatshrink tubing over where the outer cloth covering ens to prevent it from fraying.
[Image: http://farm4.staticflickr.com/3827/10603...7bf8_c.jpg]

I also found a nice spot to mount a fuse holder using ad existing chassis hole.
[Image: http://farm6.staticflickr.com/5519/10603...7436_c.jpg]

So what do you guys use for chassis bolts ? An original is on he far left. The closest modern version I could find is the sheet metal screw next to it. The tread pitch is right, but it'snot quite as snug a fit as the original. The other two bolts are the right diameter but he prong pitch.
[Image: http://farm8.staticflickr.com/7332/10603...0dd9_c.jpg]

Argh! I know I have a spare pair somewhere but can't find them Icon_sad
[Image: http://farm8.staticflickr.com/7386/10603...3645_c.jpg]
#34

You need to find a place that sells nothing but fasteners, they might have something closer then that sheet metal screw. The only other option is to break out a tap and die set and modify the holes to accept machine screws. One of the old radio parts venders supposedly sells replacement chassis screws for Philcos but I have a feeling that they are just sheet metal screws like the second ones you have.
Regards
Arran
#35

I'm calling it doe for now Icon_biggrin If I ever come across more suitable grille cloth, I'll replace the old tattered original.
[Image: http://farm6.staticflickr.com/5533/10610...5953_b.jpg]

[Image: http://farm4.staticflickr.com/3787/10610...f682_c.jpg]

I think it's a big improvement over what I started with Icon_e_wink
[Image: http://farm9.staticflickr.com/8385/86147...fcf6_b.jpg]
#36

Looks good Bob, as always
Icon_thumbup Icon_thumbup Icon_biggrin
Joe

Joe Bratcher near Louisville, KY




Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
Philco 38-7 Speaker
I have let this one sit because of other duties. Now I am back, and I have a couple of questions. I hooked up a Hammond ...tludka — 05:34 PM
Philco 42-390, code 121 speaker
>>A closer examination of the very small print schematic indicates that the speaker is a PM type. This shows a ...morzh — 05:18 PM
Philco 60 Squealing
Litz is typically tinned by simply rubbing it with the soldering iron tip while immersed in solder (and a bit of rosin f...morzh — 05:14 PM
Philco 6K7
The suppressor grid (if by G3 you mean the S) is usually at the Cathode potential, which in this caes is GND. I am not ...morzh — 05:10 PM
Philco 16B Parts
Thanks for the reply. Unfortunately the radio was removed before bidding was over so I didn't get a chance to bid.dconant — 04:10 PM
Philco 16B Parts
Hi Dan, Mike is correct, there's a lot of painted stuff on the chassis but it looks pretty good. The sm is all there,sp...Radioroslyn — 03:50 PM
1930s Stromberg-Carlson Tombstone Radio need help identifying model number
Hi Cap'n Clock, Unfortunately, I do not have this radio.  This is a shame because this should be a good performer.  2A...captainclock1988 — 03:43 PM
Philco 42-390, code 121 speaker
Using a 5W  1.5k  ceramic resistor in place of the field coil and using a 4 ohm PM speaker, I was able to bring the radi...Stevelog — 02:57 PM
Philco 60 Squealing
I have taken out the 2nd IF and found a problem or not. I believe the coils are litz wire. There is a very small strand ...dconant — 02:13 PM
Philco 6K7
I am restoring a Philco 37-60. The am reception is very good, but the shortwave is very weak. Run 6 Philco removes the g...bobbyd1200 — 01:35 PM

[-]
Who's Online
There are currently 4375 online users. [Complete List]
» 1 Member(s) | 4374 Guest(s)
Avatar

>