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Scott philharmonic fm with remote: Power supply

I joined because my question and I were referred by the Antique Radio Forum Moderator! So, here goes...

The question is:

       "Is there an expert here who can explain the differences between the power supply for a Philharmonic FM with remote, and without? As far as I can see, there is an extra plug on the side (3 instead of 2), and an extra transformer and electrolytic underneath. Does anyone have a schematic showing the differences from the non-remote power supply? An explanation why they are there? 

        "In a follow-up, I've discovered that the "third hole" is for a four prong plug connecting the power switch cable from the tuner. This was a change in the later models - presumably including those with FM. Earlier models had a separate cabinet-mounted on-off switch wired through the cable feed-in to the ps. So two holes, not three. Now, what about that transformer and electrolytic and diagram? Anyone? :P

       "Last try. Here are a couple photos to let you see what I'm talking about: One with the transformer (and remote), one without. Any thoughts?"
So, proudly I turn my confusion over to the pros from Dover! Thanks.

Attachments:
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The difference between the power supply for the remote operated Philharmonic and the standard Philharmonic is provision of the control voltage for operating the switches and motors associated with remote control.  This is an AC voltage (24-volts as I recall) and therefore the control voltage supply consists solely of the added transformer.  A socket was added to convey the control voltage to the tuner chassis.  No additional electrolytic capacitor was needed or added for the remote operation.  I do not believe that Scott published any schematic of the remote operated power supply.  At least I have never seen or heard of one in over 30-years of collecting Scott radios.

Norman

That kind of expertise can only come from seeing a lot of parts, Norman. Thank you. Where was the socket located? Top, side, inline? I suspect maybe inline, since the remote tuner I have, has an extra 3 twisted pairs terminating in a round connector and exiting the tuner back above the Cinch-Jones socket through one of the otherwise capped, pre-drilled holes. But would early AM-SW Philharmonics with remote be a guide? Or the Laureate FM remote power supply?

Tim Murphy

Norman S Braithwaite said:

The difference between the power supply for the remote operated Philharmonic and the standard Philharmonic is provision of the control voltage for operating the switches and motors associated with remote control.  This is an AC voltage (24-volts as I recall) and therefore the control voltage supply consists solely of the added transformer.  A socket was added to convey the control voltage to the tuner chassis.  No additional electrolytic capacitor was needed or added for the remote operation.  I do not believe that Scott published any schematic of the remote operated power supply.  At least I have never seen or heard of one in over 30-years of collecting Scott radios.

Norman

The socket for the control voltage is a four pin tube socket located in line with the speaker and set sockets.  The two large pins (1 and 4) are for the control voltage.  The Philharmonic power supplies for the nine control versions of the Philharmonic (revised) also had a four pin socket at this location for the AC line switch (located on a front panel control).  The pins used for the AC switch are the smaller pins (2 and 3).  Revised circuit Philharmonics with remote control had all four pins connected for both the control voltage and the AC switch.

The power supplies using the rectangular Jones plugs and sockets were used with later AM-FM Philharmonics, Phantoms, and Laureates.  I am not sure if the remote control option was available with the FM sets.

Norman

That small three wire connector coming out of the tuner goes to a plug on the speaker crossover. It will switch the tweeters in and out (they are only active on the FM band in the FM Philharmonic sets. You will see a corresponding plug on the crossover network.

Kent

Some photos might help at this point. First is the cable outs from my tuner. I do not have the ps, or I wouldn't need to be discussing these questions! Second is a pic of the ps plugs on a Phantom with remote. Unknown if this is an FM. Third is an underside shot of a Model 16 with remote. This would be AM-SW only of course.

I now agree with Norman that Laureate square style plugs were not used on my set. I think however that the ps "third hole" might have contained six pins, to match the extra tuner cable shown? This terminates with a round in-line six pin connector at about a foot in length.

I believe that the speaker cable would come from the ps, Kent?

Tim Murphy

The photos did not appear as intended. Here they are:

No. 1:

No. 2:

No. 3:



Timothy Murphy said:

Some photos might help at this point. First is the cable outs from my tuner. I do not have the ps, or I wouldn't need to be discussing these questions! Second is a pic of the ps plugs on a Phantom with remote. Unknown if this is an FM. Third is an underside shot of a Model 16 with remote. This would be AM-SW only of course.

I now agree with Norman that Laureate square style plugs were not used on my set. I think however that the ps "third hole" might have contained six pins, to match the extra tuner cable shown? This terminates with a round in-line six pin connector at about a foot in length.

I believe that the speaker cable would come from the ps, Kent?

Tim Murphy

Tim:

I don't believe the three twisted pairs are original.  I will report back after I examine my remote operated Phantom.

Norman

Thank you. The 3 pairs are certainly not cloth covered. For comparison here is a shot of the underside:

And of a Phantom ps with remote:

Tim Murphy

Tim:

We've got too many sets going at one time on this thread!  Your Phantom power supply for a remote operated set appears similar to mine.  The two large pins on the four pin plug are for the control voltage.  The small pins are for the AC line switch.  I believe this would dictate that the Phantom is the later "Deluxe" model with the power switch on a front panel control.  None of the three remote Philharmonic tuner chassis in my possession have a hole where yours has three twisted pairs.

Norman

Please forgive the photo flood. As you'll imagine. I've been chasing this power supply issue for awhile.

To summarize my understanding to here: 1) The Philharmonic FM ps has 3 side holes in a line, with the inmost 4 pin tube socket-style hole devoted to main power and to 24v ac control motor power; 2) there is one added transformer mounted on the underside of the ps along the same side as the 3 side holes; 3) there are only two connector cables between the ps and the tuner; 4) no additional "motor start" or other electrolytics are involved; 5) the connectors are all circular multi-pin, not square Cinch-Jones; and 6) there are no schematics readily available for the remote modifications.

   The question what is going on with the extra 3 twisted pairs out the back of my FM tuner with remote is unanswered, although the wires appear to be a non-production addition, and the underside photo of the set does not explain their function.

So there is one more and final question (for now anyway): The various attached "power supply with remote" photos, including of the Model 16, the Phantom, and the Philharmonic, all seem to show the same transformer. What are the specs, maker and/or part number of this unit?

 Thanks again for the chance to make progress on this challenging bit of research.

Tim Murphy

Norman S Braithwaite said:

Tim:

We've got too many sets going at one time on this thread!  Your Phantom power supply for a remote operated set appears similar to mine.  The two large pins on the four pin plug are for the control voltage.  The small pins are for the AC line switch.  I believe this would dictate that the Phantom is the later "Deluxe" model with the power switch on a front panel control.  None of the three remote Philharmonic tuner chassis in my possession have a hole where yours has three twisted pairs.

Norman

Reviewing the thread, I see at least one amendment needed: The pictures show the transformer mounted opposite the cable sockets in the Philharmonic ps, and on the same side for the Phantom. It certainly illustrates that Scotts were handmade.

Tim Murphy 

Tim:

The Scott part number is stamped on the cover near the top edge.  It is a number in the 5000 range.  This transformer was most likely made by the EH Scott Radio Laboratories (formerly Scott Transformer Company) and, unfortunately, we do not have the exact specifications.  Transformers from other companies providing control voltages, fortunately, are not uncommon.  When I have time I should energize one of the control transformers and determine the voltage.

I was unable to speculate on the purpose of the added three twisted pairs due to the small size of the photo.  If you can post a large close-up photo showing where these wires are hooked into the circuit, I can speculate as to their purpose.

The control transformers in your chassis are where they are normally found for the particular models.

Norman

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