Progress feels good- '59 Motorola - Videokarma.org TV - Video

Charlie · #1 11-30-2006, 09:24 PM

Quite often, it seems I always have "half-finished" projects sitting around just screaming at me to finish them. I suspect that many of you know exactly what I'm speaking of. I also suspect you get the same good feeling as I do when FINALLY getting around to finishing one.

Here's a little number that's been sitting on a table... partly disassembled... and I finally got tired of seeing it that way. It's a '59 Motorola 21" series-strung table set. I got it nearly two years ago... it's main problem back then was a near-dead CRT. I found a tube for it in another similar styled set... the emissions nearly pegged the meter... and after swapping them out, I got a pretty decent picture out of it. The chassis still needed some work, and it sat on the table pulled apart for all this time... till a couple of days ago when I got some caps for it. After replacing the lytics and tubular-ceramics, it performs pretty good and I'm glad that I was finally able to put it all back together again. I've been watching it for nearly two days with no troubles and no smoke!

Here it is sitting on top of my Philco Diamond D. The Motorola doesn't make quite as sharp a picture as the Diamond D, but it does pretty good and it's far better than the day I first brought it home.

bgadow · #2 12-01-2006, 12:09 PM

Looking great! You may recall I have the twin to that Motorola...a royal pain to work on the chassis, but a good performer. Mine is probably my best running 21" bw set (which just goes to show I need to spend some time improving the others!).

Charlie · #3 12-01-2006, 01:24 PM

Bryan, yes I remember you having one of these... and remember talking about it being such a pain to take apart. After changing the CRT nearly 2 years ago, and working on the chassis this past week, it seems to me that it's only a pain to take apart depending on what you have to do to it.

No, the chassis doesn't simply slide out the back. Changing the CRT requires taking all of the side panels apart and the front bezel as well. You only need to take it this far if you're changing the CRT. Getting to the tuner nearly requires this. As far as chassis repairs go, all that's involved UNDER the chassis is removing the screws that hold the bottom panel on. Turn it on it's side and you can get to everything under the chassis. Since everything stays together other than the bottom panel, it makes it easy to turn it on and look after changing each cap, resistor, or whatever your changing.

The Motorolas of this period could have had better tuners. It seems the tuners they used got flimsy easily. My b&w floor model Moto has the same flimsy tuner as this set. I also had a parts Moto that had the cheesy tuner.

bgadow · #4 12-01-2006, 04:01 PM

I was going to mention that-the tuner on mine doesn't have any "click" at all, real sloppy. Works, though. Hey, I didn't realize that bottom panel came off seperate-glad you mentioned it! I guess I wasn't looking at it right. There are a couple caps I should have replaced and have been kicking myself for not doing it. Until it warms up the vertical has to be adjusted. Being it is fairly simple I will go ahead and do that soon.

peverett · #5 12-01-2006, 08:24 PM

From what I have seen of Motorola sets in general is that they like to use cheap "wafer type" tuners. I have yet to see one with a drum type tuner. It has been my experience that these types of tuners do not work all that well, even after cleaning.

The old Hoffmans, Admirals, and Emersons that I have contain the drum type which, once cleaned, seem to work well. I even have a Hallicrafters radio with a band switch that is drum type like the TVs.

fujifrontier · #6 12-01-2006, 09:46 PM

what is a wafer tuner?

peverett · #7 12-01-2006, 10:20 PM

In the 1950s and 1960s, there were in general, two types of TV tuners, the wafer type and the barrel type. The wafer type are similar to the bandswitches in most antique radios, with the switches in "wafers". These can be cleaned somewhat with tuner cleaner and possibly a Qtip, but if the switch metal is losing its strength, they could need rebuilding with new switches to work.

The barrel type is fairly unique to TVs. I have only seen the Hallicrafters radio that I have that uses a barrel switch. In a barrel tuner, there is a drum (shaped like a barrel) that contains a strip for each channel. On these strips(inside the barrel) are mounted the inductors, etc for each channel. 1/2 of the contacts needed for each channel are also contained on the outside of the strips. Once you remove the TV tuner cover, these contacts are easily cleaned. As the strips are generally removable, some can be removed to allow cleaning of the contacts connected to the main portion of the tuner. This also allows easy replacement of defective strips.

In my experience, the barrel tuners work much better over time than wafer ones. The do cost more to produce which is why some TV manufacturers did not use them. I have always seen wafer type tuners on Motorola sets. I have also seen them in some RCA sets. I have seen the barrel types in some Zeniths, but am not sure that they did not use the wafer type also.

fujifrontier · #8 12-01-2006, 10:48 PM

thank you