The Fine Things are Always Hand Made
I had posted this at the bottom of my post for the Crossover Box, thought I'd put it in a new posting.
After a few false starts (a very long story), I ended driving out 2 weeks ago to pick up the AM FM Philharmonic. The set did not have a cabinet so it wasn't to difficult to load into the CRV. Its dirty, a lot of nicotine, some of the larger cans on the tuner have some chrome bubbling and some of the smaller square cans have some small dents, but once I get it cleaned up it will be OK, not mint, but nice.
Kent, the tuner serial # is LL-471 and inside the Amp chassis is a hand written RR-339.
2 surprises, one OK, the other disappointing. The baffle had a Tauscher board installed. Nice to look at, but akin to putting a curtain over a lighthouse. The other was that one of the tweeters has an open voice coil. I did talk to Nick Dorazio at thespeakershop.com, he does not have any more materials to redo the cone. His concern is that in removing the cone to re-coil it, the cone could get damaged. Looking for suggestions to have someone "recoil" it and hopefully be able to save the original cone and surround.
The speaker connector on the amp was replaced with an octal, and the speaker plug was replaced with a 9 pin "octal" style plug. The crossover box was long gone, so I can only guess why these plugs/sockets were changed. I'd like to get the amp back to stock, I know the speaker socket was a smaller pin circle than the one for the tuner, and the 2 large pins were opposite each other as opposed to next to each other but could I rework a 6A7 style wafer tube socket which is the small 7-pin for this? Of course if someone has a chassis they are parting out please let me know.
The filter caps were replaced at one point, will try to decipher the info on the cap to get the manufacturer and date code. But they all measure good (capacitance and dissipation). It'll be a while before I attempt to power the set up but will reform the caps first and recheck them before going further.
Lastly, I'm missing one of the round wooden knobs, could use 2 as one is in poor shape. If anyone has some please let me know.
I'll post some pics as I get it cleaned up, and I'm sure I'll have more questions as I dig into it.
Not unusual for the tweeters to be mounted so high behind the console grill that the cabinet obscures a portion of the tweeter cones. Does not seem to matter.
I have an original round S knob I can spare.
Forrest, thanks for the offer, I was able to locate one so I'm good on that.
Still looking for the special 7 pin speaker plug if anyone has an extra. I could also use the wafer style socket, but I can make a socket up with a conventional pinout 7 pin socket.
Still looking for the 7 pin speaker plug & socket, so I thought I'd expand my request to include the AW23 sets. I realize they are not the same, but it would "look" original. If anyone has one or both, please let me know.
As an alternative, I'd consider the power plug and socket from the AW23, Phantom or Philharmonic, understanding there is the risk of accidentally interchanging them.
Am finally working on the Scott.
Some of you will disagree with my method, but when do a project like this, I try to bring up the set to a state where I can assess what works and what doesn't. There are some that prefer to dive deep into it - replace all capacitors, resistors as required, etc. without even trying to power it up. But, unless its a basket case I prefer my method.
So with that said, I verified the electrolytics were OK (they had been replaced at some point), the chokes and transformers good, and then slowly powered it up monitoring input voltage & current, B+, C- voltages, and of course keeping a close ear for odd noises from the set and speaker.
I was very pleasantly surprised that the AM & SW bands work. With no antenna, was able to pick up WTMJ (620) and with a 4' wire (in my basement) got several AM stations. WTMJ was exactly at 620 on the dial, not 619, not 621, right at 620. Was also able to get WWV at 5, 10& 15 Mhz, again, pretty much dead on the dial.
FM does not work, found a burned open resistor in one of the IF stages, and another resistor that was replaced but at 10x its original value. Will have to get to that...
The AM AGC bypass caps were replaced at some point, why only those I don't know. The 6F8 was replaced with a 6SN7 and a kludge adapter socket, but it is functional, the 6H6 sensitivity tube was replaced with 2 diodes on a plug. Those can be put back to stock.
Here's my dilemna - The Selectivity pot's wiper is not contacting the element. If I pull on the shaft it works. So I want to remove the pot to fix it (the back cover is removeable), but it looks like I'll need to disassemble the entire front of the Selectivity mechanism. Any tips or short cuts?
Is there a mechanical positioning (alignment) of the selectivity assembly relative to the pot? i.e., with the pot fully CCW is there a position the trimmer capacitors should be?
Oh, I did spend some time cleaning, here's what is looks like:
Would appreciate any tips on the removal of that selectivity pot.
That set looks beautiful.
I am with you on powering up the sets. I just go over the electrolytics (usually just replace them) and bring set up carefully. If it comes up, you can work a section at a time making sure it still works when you are done with that section. If it doesn't come up, you can troubleshoot to get it working, then start replacing capacitors. Normal leakage due to age does not stop a radio from working in most cases.
As for the selectivity pot, just turn it to one end and return it in the same position. Mark the selectivity main gear on the shaft to make sure it is in the same position when you reassemble.
Karl - Looks very nice.
I am "in the replace all the paper/wax caps" camp. Just do not want the suspense of delayed cap failure. And figure a host of leaking caps on the B+ just stresses the high voltage circuit by drawing extra current.
My current project is the 1941 Scott Laureate with original filters. I did replace the two 500 volt rated filter caps with new. But explored reforming several in the lower voltage B+ circuits, and was pleasantly surprised they all reformed very well using my restored EICO capacitance-resistor bridge.
Powered up and played pretty well, including the old FM band using a frequency shifter for new FM.