Motorola 16VF8
 

My son spotted this on CL last night. We picked it up this afternoon near Fox Lake, IL. It uses the TS-16A chassis and a 16AP4. Sams' folder 93-7.

More pictures. The cabinet is wider and taller than my Dumont RA-109 A3 Sherbrooke, but not as heavy.

These are the pictures the CL lister emailed me of this set before I picked it up. They were taken before the set was put in storage for awhile. The left upper door hinge and cabinet hadn't been damaged yet. Last picture is from an old 1949 Motorola advertisement.

Great find! I like the color and design a lot. The chassis reminds me of the 19K1 I work on a few years ago: http://www.videokarma.org/showthread.php?t=248133

I imagine not many of these survive. Motorola also had a 19" version of the set. Model 19F1 the "Gainsborough". Same cabinet style but possibly even larger.

The date code stamped on the base of the CRT means it was probably replaced at some point, hopefully still good.

Nice score, Ed!

That is one of the classier looking 50's combos.

I hope the CRT is OK also. The craigslist ad stated " everything works". The HS-211 AM/FM/phono chassis has it's own power transformer with a 6V6 P-P output.

Took a chance after testing the power transformer AC voltages today. I slowly powered up the set with the two 5U4 rectifiers and a new 1/4 amp fuse in the horizontal circuit. I got a fairly bright horizontal line across the screen. At least I now know the CRT is usable. The vertical was trying expand but,it looks like that won't happen till I do the recap. This set does not use a vertical output transformer, direct drive to the vertical deflection coils.

Well after recapping three RCA tv's in January, KCS-28,45,and 47 chassis I started on the Motorola TS-16A chassis. This set has turned out to be a great learning experience. The TS-16/16a and TS-30/30a chassis sets from 1949 were the only sets to not use vertical output transformers for a magnetically deflected CRT. This chassis uses a 35Z5 damper tube with a hum control, an audio squelch circuit,and a high voltage regulator circuit for the crt.
After recapping I started testing the set and found I had intermittent HV of 8Kv. This set uses two 1B3s, doubler. It was also red plating in one of the two 6BQ6 horizontal drivers. The problem was the 3 wire horizontal blocking transformer. It had an open winding. I opened up the transformer and was luckily able to re-solder poorly scrapped magnet wire.
With the horizontal oscillator now working, I measured 12KV at the anode lead.
Only trouble was I still was't getting any light or raster of any kind on the crt. I use a 5AXP4 for testing. All the voltage to the crt tested fine except one, the G2. Turned out the B+ boost voltage for G2 was not being boosted. This set used a selenium rectifier to boost B+ for G2 only, I had to replace that too. After the boost fix , I finally was able to get a bright horizontal line, but no raster still. I limit the mains voltage when I first start up a set.
I started checking the vertical oscillator and output tube circuit on the scope. Wave forms were fine even at 6BQ6 vert. output. Now I was worried the problem may be the deflection coil. I unplugged the yoke and found the 2 vertical windings to measure 43k ohms in series. They should have read 920 ohms in series. The horizontal windings were OK. They read 21 ohms.
After doing some checking, I found this chassis seems to have a one of a kind deflection yoke. None of the coil manufacturers' lists a cross of any type.
In a last ditch effort, I decided to cut open the cardboard yoke cover to see if maybe a wire came loose.Some of the vertical coil wires were corroded or broken. I was able to repair one section of the vertical windings but the other was broken some where in the windings.
With one vertical winding section still intact, I took inductance and resistance measurements, with the 36k ohm shunt removed. One section of vertical coil measured 382 mh and 463 ohms. I also measured the horizontal coils. They were 7.24 mh and 10 ohms each. These vertical and horizontal measurements were with an iron core yoke.
Needing a yoke with a vertical inductance of about 800 mh and horizontal of
about 16 mh, left me only a few choices since I wanted to get this set working again. I could re-wire all the vertical and horizontal circuits to match a latter version of this chassis, a TS-67, or try and rewind the vertical coils of the yoke. I decided to try and re-wind the yoke.

Continued:

I slowly took the coil apart to avoid breaking any coil wires. The original internal tie points were riveted to a paper band. The paper was so dry,it just crumbled to pieces when touched. After taping off the wires and removing some layers of tape I got to the iron core which surrounds the windings. The iron core is nothing but annealed black steel wire. The old core was very rusty and weighed about 6 ounces.
With the iron core removed along with some more tape layers, I reached the now exposed vertical deflection windings. Fortunately the vertical windings are covering the horizontal coils, which I didn't want to remove.I used plastic tools to pry loose the old vertical coil. I didn't want to damage the horizontal coils underneath.
With the vertical coil and iron core removed I re-measured the inductance of the still intact vertical and horizontal coils. The vertical coil has an inductance of about 266 mh. The horizontal coil is 5.5 mh per section. I now had a starting point from which to wind the new vertical coils. I decided to do both vertical coils, since I didn't know what caused the original coil break, stress or corrosion.

You're a braver man than I. It never even occurred to me that you could rewind a yoke. Here's hoping it comes out OK, that is an interesting and beautiful set.

That’s really a nice looking set. That’s one of the high end Motorola’s of it’s day where both big yellow knobs light up!

Gosh, what a labour of love! I applaud your efforts and sincerely hope it works out. Please continue the pictures and let us know how it goes.

I dug up the service info for this chassis and reviewed it. Very cool! I had no idea Motorola had a chassis with innovations like a regulated HV supply.

Unfortunately, that leads to oddball parts like the yoke. Good luck with the rewind. I think it will be worth the effort to bring this set back to life.