Amptech Systems & TUBETVSHOP.COM

&

 

This is a beautiful set that I bought recently on eBay from someone who has become a great friend (Thanks again, Tim!).  When I received it, it was already in very good condition and needed very little work.  With some light dusting and a Pledge Wipe,  the shine returned to the beautiful finish. 

After thoroughly dusting the chassis, re-forming all of its electrolytic capacitors and testing a 10% statistical sample of all resistors and paper capacitors, I discovered that the set was in even better condition than I had expected.  I then took resistance measurements for comparison to the chart in the Sams folder for the electrically-identical Fada model 799 (since Sams never issued a folder for this set).  Replacing a few weak tubes, I connected a Variac, an ammeter, some DC voltmeters, a high-voltage probe and an oscilloscope.  After taking some measurements and evaluating some key waveforms, I checked the RF and IF response curves against the Fada alignment data and determined that the chassis was ready for reassembly.
Here is the set, reassembled with its picture tube and being tested live.  It looks like all it needs are its final adjustments (yoke, focus coil and ion trap positions, width, height, linearity) to produce good picture.  The picture is actually looking surprisingly good for a 100% original set at the ripe old age of 53 years even before these adjustments.  
After final assembly and adjustments...powered down for the moment to show off the beauty of the cabinet.  This is a great piece of furniture.
This set is a 1949 model, but the dial starts with Channel 1 and ends with Channel 13.  History lesson --  Channel 1 was dropped in 1948.  This was one of the last 13-channel sets to be produced.  It's an early-production 9-408, serial number 273. 

Here's the set once again with power on and working very well.  The camera's flash brings out the beauty of the wood, but isn't very flattering to the picture.  Overall, though, it's a well-preserved antique in remarkably fine original condition.  This case proves that restoring vintage electronics doesn't always require mass replacement of components.
One more view of the set showing the presence of the original rear cover, high-voltage cage and NOS exact-replacement power cord.
 

Test Equipment Used During This Restoration

Analog VOM -- Simpson #260 HV Meter -- Lectrotech
DMM -- Micronta #22-195 Ammeter -- Amprobe
VTVM -- RCA #WV-77E Tube Tester -- B&K Precision #707
CRT Tester -- B&K #465 Sweep/Marker Generator -- Precision #E400
Capacitance Bridge -- Sprague #TO-4 Oscilloscope -- Tektronix #547

 

 

 

 
 
Send mail to webmaster@amptechsystems.com with questions or comments about this web site.
Last modified: 07/06/17