Philco 48-1001 - 1948 vintage

[John Folsom]

Dave,

Pretty sure I can help with the 4 pin connector. When it comes to it. you can simply strap the L & H band inputs in parallel, only one of the 2 input lines is terminated at any given channel.

It is not uncommon for an old 40s vintage set to come back to life when brought up slowly on a viriac, but it will not last. A full recap is the only long term solution. I am sure Chuck A would love to do it. :-).

No fine tuning required, as the AFC control loop in the set keeps the tuning perfect! Don't know why other manufacturers did not adopt the concept.

I was never very fond of the Philco 8 position tuner, but the reasoning was sound. Back in the 1940-early 50s, there would never be more than 8 stations in any given major metropolitan area, as decreed by the FCC. So 8 was enough.

That is a great set. Same chassis as the somewhat more stylish 48-1000, but still a under-appreciated set, in my opinion.

[ChuckA]

Originally Posted by John Folsom

Dave,
A full recap is the only long term solution. I am sure Chuck A would love to do it. :-).

John / Dave,

I think I'd rather trade you a restored 1001 than get into another one of those.

Only 73 caps to change.

The antenna connections are separate on each of the tuner "plugins", pins 3 & 7 are LF and 4 & 6 are HF. To eliminate interference Philco recommended shorting pins 4,5,6 together on the HF plugins, and 3,5,7 on the LF plugins.

Also for areas with low signals there was a "Channel Adjuster" kit available. Consisted of a dual pot and switch assembly, it added a voltage divider to the contrast control that allowed you to manually adjust the voltage on the AFC bus from negative to zero to positive.

Beam Bender was Philco speak for ion trap.


Chuck

[Eric H]

Originally Posted by ChuckA

Also for areas with low signals there was a "Channel Adjuster" kit available. Consisted of a dual pot and switch assembly, it added a voltage divider to the contrast control that allowed you to manually adjust the voltage on the AFC bus from negative to zero to positive.



Chuck

Someone was selling some of these kits NOS on eBay for a while, I tried to get one but was always outbid, couldn't understand the demand for something that only a handful of people would need?

[ChuckA]

Originally Posted by Eric H

couldn't understand the demand for something that only a handful of people would need?

Eric,

I doubt it was something many people wanted in 1948 either, I have a few NOS units around here someplace also.


Chuck

[forjack842]

Finally finished the 48-700 electrical restore. A bit of fun with the HV caps. Tall one shorted about 3 hours after the 3 day long variac power up cycle completed. Typical!! Metal HV oil cap under chassis arced internally often enough to be a pain so it was retired. Big one stayed inplace disconnected, the oil one gone. 0.1uf Tesla caps are available to 10kv and fit nicely under the chassis. 6kv one for the video coupler also available and cheaper. All a bit pricey, but readily available on Ebay. Definately do not want to get across those 10kv'ers!! The rest was standard cap, resistor and wire replacement. Video and Audio alignment went perfectly. Used a Leader 480 U80 S&M. Does a nice job in the 24Mhz IF. John F helped me with a few tuner strips. Had to rewind 2 to get on freq. I needed ch 2 4 and 6 for my home TV 3 channel station. Not worried about any 2009 digitial BS. I'm still very low power analog throught out the house. 4 servers, 1 RAID, 3 agile modulators, KMPlayer and bingo! 24/7 RF to rabbit ears. Just like the 40-50's! Love XPMedia Center and Xvid...all the old programing all the time.

Anyone have a source for the tuner number/stars repros?? Might be able to scan them in.
Jack