The Fine Things are Always Hand Made
What schematic best represents the BOL Philharmonic? The schematics I find seem to be for the pointer dial. How much difference is there?
Also, my BOL has had roughly half of the capacitor changed using mostly Solar brand. I presume this was done quite some time ago and was wondering how good these capacitor were/are. The radio works and is quite sensitive, but there are quite a few problems so I'm thinking of recaping the whole thing. I wish I had all of the originals so that I could restuff them!
One other note re: the little 5 pin socket on the back of the later Philharmonics and Phantom Deluxe models:
Later sets in the FM era, the socket was wired to the band switch to control the tweeters, after spring 1940 when the optional 4 unit speaker system was introduced.
But previously, an identical looking small socket was the phono input plug.
So - if your receiver has the little socket, best trace the pin wiring to determine if it is for
1) phono input audio or 2) tweeter control from the band switch.
And always remember - Scott was a custom set builder, and evolution of a model occurred.
Mostly finished! I re-glued many joints in the cabinet and then reinstalled the radio.
I spent many hours playing with the IF alignment using my spectrum analyzer. It was fun seeing the response curve throughout the range of the selectivity control. I found that IF AGC voltage has an affect on the response curve. I experimented with many stations, measuring the AGC voltage. Turns out that the recommended -15 volts works out about the best.
This is the first Philly I've played with. It is awesome! The best sounding radio I have, including the Masterpiece VI with custom speaker system. I've been playing it for several hours now with a signal from my "HIFi transmitter" and computer DAW. Love it! Next is the Garrard turntable.
Is it usual for this radio not to fit the cabinet properly? The radio hangs past the back of the cabinet by about 1/2 inch. Plus, the amp has to have plugs facing to the back rather than toward the speaker or it won't fit without hanging over the edge.
Congrats Rob, nicely done, you now have a problem, nothing else will compare to your philharmonic, they do sound superb.
I have an old auto fm to am converter running on mine, modern FM sounds really nice, you can tell it's not an am transmission,
The variable if on shortwave transmissions is really useful, it's nice to have the facility to adjust the bandwidth and sensivity, at a pinch you can even stop hetrodyning between stations.
Earlier you said that the transformer ran warm, my radio is a 60hz model running on 50hz through an auto transformer to step our 240v to 110v, the transformer runs at a measured 105F,
this is after 3 hours of playing so you could take this as worst case, don't forget the transformer is right next to the rectifiers, there is 60w of heaters there.
Thanks Mike! Yes, I am aware of the heaters next to the tranny. I should get my IR temperature sensor out but I'm not sure how well it will measure on chrome. I could aim it through one of the vent holes. For now, all of my radios are fed by a direct RF connection through my antenna system to my HiFi frequency generator/modulator. It is not a transmitter, rather, it could be used to drive a linear amplifier for a transmitter. It puts out just enough signal to couple to my antenna system to provide all of my radios a fairly weak RF signal. I have tested its frequency response to be at least 20hz to 15k hz. Gives a great sound through all of the "HiFi" radios (Masterpiece VI, this BOL, 37-116 and 38-116 Philcos.) I also have an FM transmitter so that I can receive the program material on my Scott 16A on both the FM band and AM band.
One of the problem I have on all radios of this vintage is getting a good blend of highs, mids and lows. If I get the highs where I want them, the high mids are too pronounced and harsh. The Philly is the best so far because I can play with the sensitivity to get the volume control in an area relative to the tap to get the best balance. The tweeters allow a bit of "shimmer" on snares and cymbals without accentuating the high mids into an area of harshness. I'm liking this radio!!
I've been playing this radio for several months now. it occasionally emitted a bit of static so I finally decided to see if I could solve the problem. I replaced all of the Solar caps and a couple of Sprague Black Beauties that had been replace previously. It's been playing for several hours now without a hint of static. Since the last Solar caps were made in about 1949, it is understandable that they may cause problems. Turns out that when Solar went bankrupt, they had huge inventories that went to a lot of supply houses. Solar caps were being sold as late as the early 70's. So now I have a whole bunch more of the Chinese yellow caps visible under this radio! Oh well, it performs admirably.
Thats good news that you have finally got things sorted out,
my Philharmonic is full,of orange drops, this was done probably back in the seventies or early eighties, but the more awkward ones were not done, I tend to disguise the yellow caps by making cardboard tubes from broken paper,
I made this for my allwave fifteen, not original but fits in well.
The text is supposed to be brown paper.
I have done that as well. In fact, there are a few that I made in this radio when I was working on it back in May. this time around, there were about 25 caps that I replaced and didn't feel up to the task of making a bunch of paper tubes. I just wanted to get the radio back up and running! I know a lot of guys here don't bother. I usually do and will on the AM/FM where needed. But for now, I'm back enjoying static free reception.
I save all the original caps when I recap a set and then I melt the guts out and reuse the tubes for restuffing. This gives me actual original cap bodies for a rebuild. I don't do it for every set I work on, but if it is a very rare set or has historical significance, then it gets the treatment.
I just did a Philharmonic amp this week with the Solar Sealdtite caps (just 2 of them) but they are a hard plastic type material and just not easy to restuff. You would have to get a new tube and just transfer the label. But on wax caps, I have melted the guts out plenty of times and then sealed the ends after the new cap went in with bees wax.
Any of the caps in this radio that were still original received the re-stuff treatment. I just isn't that hard to do. I dislike the looks of the Chinese yellow caps. However, when the originals are gone, one has to resort to Mike's strategy, as I have done also. But since there were so many and I wanted the radio working very soon, yellow it is! I don't have a huge inventory of old caps to re-stuff and the ones I do have say Zenith or Philco on them.
Mike, I don't think I have ever seen a "Scott" capacitor! I like it.
So apparently, the yellow caps are now being made in black, to accommodate us old radio folks. I believe I saw that on Sal's capacitor site...