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-   -   Tubes/parts needed to get a Philco 50T-1406 (http://www.videokarma.org/showthread.php?t=252738)

mpatoray 11-29-2011 08:14 PM

Tubes/parts needed to get a Philco 50T-1406
 
Hi all,

Im looking to start on the Philco TV I picked up at the ETF in Hilliard.

I need a few tubes to get it going, some where missing some tested bad.

I need the following tubes;
6SN7 2x
12AU7
6AU6

Also the speaker cone is trashed so i think I am going to need a speaker.

The flyback looks good and at the ETF had a chance to test the 12JP4 which tested near 100% in emission/life test. It also looks like someone started recapping in the 70's.

Any help would be appreciated.

Matt

electroking 11-30-2011 11:46 AM

What's the problem with getting those very common tubes? If you insist on buying
them in person, rather than by mail, just go to any decent hamfest around your area.
Good luck with the project!

bgadow 11-30-2011 10:53 PM

I am strictly lo-fi so I don't know much about tube audio, but the 6SN7 & 12AU7 are desirable enough to audiophiles that I don't have any spares. Seem to be plenty of 6AU6s, though!

I have a similiar Philco and had to go through a half dozen 6SN7s in the vertical circuit before I found one that would work. The tubes checked okay, it was just that this set was very picky.

47'Plymouth 12-02-2011 03:42 PM

Matt;
PM in Private I'll send some tubes to replace what's missing:yes:with address:banana:
Jody....driving 2.5 tons of Antique post-war Mopar Fun:banana::banana:

mpatoray 12-26-2011 03:24 PM

5 Attachment(s)
Thanks to some Video karma members and Just Radios, i have started work on the Philco TV.

The first thing was to clean up the chassis, then insert all tubes except the 5U4 rectifier tube so could power up without the HV. So i ran up the variac up slowly over like 45 min just to see if the tubes lit and the power trans did ok without heating up.

After that went ok i inserted the 5U4 and did a slow power up over an hour and a half and was rewarded with a raster.

After that and getting schematics and a service manual I ordered replacement caps form Just Radios, they did not have all the cap values i needed but i decided to place the order to get started.

The caps came in on Thursday and i decided to take time this long weekend to start recapping in stages, replace 5 then power up to make sure no harm was done.

mpatoray 12-26-2011 03:28 PM

5 Attachment(s)
Here are some of the picts of the first power up, the recap and the progress

mpatoray 12-26-2011 03:31 PM

2 Attachment(s)
Final set of picts for today, showing the progress. First pict is the first semblance of a picture I got after hooking the LaserDisc player up through RF, the second one is after

Electronic M 12-26-2011 04:32 PM

That is some good progress you got there!

miniman82 12-26-2011 07:40 PM

Those round tube Philco sets make one of the best pics out there, IMO. The one I had gave a very sharp picture, great detail. I had to have more than 4Mhz video bandwidth, but mine was a split chassis.

mpatoray 01-09-2012 11:21 PM

2 Attachment(s)
After quite a few more old junky capacitors where replaced, here are some more progress picts. The first one is the underside, an the second is the picture I got after the latest round of cap replacements.

The video comes form a Pioneer LaserDisc player with the RF modulator set to channel 4. The disc is LaserVision Demonstration II. A very high quality Japanese produced LD. Using 35mm film Betcam SP tape and HiVision videotape sources.

Electronic M 01-10-2012 12:41 AM

Woooow!

mpatoray 03-28-2012 01:26 PM

Hi all,

After replacing caps and making progress, resistors started going bad... Some i broke the leads off of when replacing other caps, the wire seems very fragile. Other caps started drifting badly the more the set was used. So Started replacing the larger higher power resistors first.

Now I am having issues with the horizontal locking in, it gets close but will just not make a nice straight picture without waving. I noticed that there are horizontal frequency and horizontal stability controls and wondered if I might start there.

Also I would love to take a scope to this thing and make sure my waveforms are correct, but there is a big problem and that is the CRT and yoke are mounted permanently in the cabinet, so if I take the chassis out I have nothing to connect it to...

Using a LaserDisc player as my source, have attached a picture of the effect. It is Jose Caracas singing.

Once the electronics are done I am not sure what to do about the photo finish which is badly marked in places.... but working order electronics are the order of the day first.

Matt

mpatoray 03-28-2012 01:27 PM

1 Attachment(s)
Well lets try the picture again.

mpatoray 05-27-2012 09:58 PM

Hi all,

First of all I would like to thank all of you who have helped me on this set. Some things got in the way so it was on the back burner, digging back into it soon and I have a question, I was told to replace all of the mica caps in the horizontal and vertical section as i can not get things to stay stable and all other paper caps have been replaced. For the replacements what type of capacitors should I order.

Matt

Phil Nelson 05-27-2012 11:09 PM

I replace mica with mica, available from http://www.mouser.com/ (and other suppliers).

Have you worked through the horizontal adjustment procedure in the Sams manual? I'd try that before replacing more capacitors.

If that doesn't help and your problem is limited to horizontal (that is, you have good vertical stability), then I'd replace only the horizontal caps and see where that gets you.

Phil Nelson


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