Quote:
Originally Posted by earlyfilm
For the two Steve's, there are minor differences noted between apparent factory schematic at
http://earlytelevision.org/tv_schematic_diagrams.html
and the Rider one at
http://bs.cyty.com/menschen/e-etzold...andrea/1f5.htm
with the first one seemingly the older version of the set.
My thoughts when seeing Dave S's first post yesterday was the thread was going to quickly turn to speculation on whether or not that this set had been converted to NTSC picture standards, or was out of service by 1941. Now that we are up to post 37, I'll just casually mention this question.
441 or 525? How many installed channels does the tuner have?
Jas. |
In Nov 1941 Andrea put out an upgrade kit and 3 page instruction sheet to convert the 1F5 to the new standards. It included new antenna & oscillator coils and a new sound IF transformer in addition to a few new resistors. Reading through the instructions the tuner coils were changed to allow the tuner to receive the "old" new channel 2 at 51.25MHz & new Channel 3 at 61.25MHz.
The conversion did not add an FM detector to the audio circuits, the new sound IF transformer allowed the set to be tuned easily for slope detection for the new audio standard FM.
The instructions describe tuning the audio first to 8.25MHz and final adjustment is peaking the audio at 8.15MHz
Also included was an extension shaft and knob to make the sound sensitivity (fine tuning) control accessible from the outside.
So if a set has the FT control knob on the right side of the cabinet there's a good chance it has the mods.
Chuck