View Full Version : Halolight flyback?


miniman82
10-19-2017, 11:16 AM
I recently picked up a Halolight but unfortunately it won’t make any HV and fails ring test after recap. If anyone has a Merit HVO-54, Thordarson FLY-76, Triad D-49 or other suitable replacement please let me know. Chassis is a 1-533-8.

snelson903
10-19-2017, 01:10 PM
i might have a thordarson 76 , ill look tonight.

miniman82
10-19-2017, 09:14 PM
Thanks for looking Steve.

snelson903
10-19-2017, 10:01 PM
sorry, thought i might have one ,been collecting as many as possible .

Eric H
10-20-2017, 01:47 AM
Does it look like this?

http://videokarma.org/attachment.php?attachmentid=195791&stc=1&d=1508482050

miniman82
10-20-2017, 10:36 AM
That’s it!

Eric H
10-20-2017, 11:53 AM
It's yours for shipping if you want it.
P.M. me with your address and I'll get it sent.

miniman82
10-20-2017, 12:23 PM
Wow, thanks Eric!

miniman82
10-20-2017, 08:08 PM
Just to make double sure the old fly is bad I subbed in an air core HV transformer, which immediately made a nice fat arc. So the old fly is definitely bad, must have a primary short since it’s all discolored in that area like it got really hot.

I’ll post a shot of this set running next to my Saratoga, soon as I get a decent picture on it.

miniman82
10-23-2017, 07:37 PM
Part received, thanks again Eric. Any chance there’s a wiring diagram for the HVO-54? Not really sure how it goes in.

Eric H
10-23-2017, 09:10 PM
Part received, thanks again Eric. Any chance there’s a wiring diagram for the HVO-54? Not really sure how it goes in.

No, I looked through the box it was in and didn't find it.

Kevin Kuehn
10-23-2017, 09:17 PM
If someone has a Merit catalog it likely would show their fly types schematically with the terminals numbered.

miniman82
10-23-2017, 09:45 PM
Never mind, there was a terminal conversion chart in the back of the Sams. Next issue is I’ve only got 6kv, I’ll play with it a little more this weekend.

miniman82
11-06-2017, 08:53 AM
HVO-54 is installed and working, but it’s only making around 7kv of anode voltage. Anyone know if this particular fly is OK to use with low B+ chassis, or does it need 385v like other sets? Sweep width is good, output tube draws around 160ma, just low HV.

Eric H
11-06-2017, 10:49 AM
I noticed that Fly had been soldered on before I sent it to you, I wonder if it could have been a dud from the beginning?

tom.j.fla
11-06-2017, 12:19 PM
Have a ? . Did you ring the fly you got from Eric H. It could be the wrong one or fil. voltage for the 1B3 is low or the 4.7K resistor in hv line is way high in value don't forget the 15 ohm resistor that's between the damper section and H. output plate section of the flyback. All the best, Tom.J

miniman82
11-06-2017, 12:40 PM
I don’t think so Eric, if there were anything wrong with it then it would have failed ring test or not worked at all. Boost voltage is low as well, there’s not much bootstrapping action going on. That’s what leads me to believe it needs more B+ in the first place, but I know nothing without seeing the spec sheet. I could see this exact thing happening if a fly was fed half the voltage it should have, but again I need proof.

wa2ise
11-07-2017, 01:17 PM
Maybe you have the horizontal output tube plate connected to a wrong terminal, in that the output pulses are going thru too much of the flyback coil. That would lead to lower high voltage and lower boost... :scratch2:

Check with an ohmmeter (with the set off) and see if you find a terminal around half the resistance than that you have the output tube plate connected to. That terminal might be the one to use. If you do change something, test fire up the set and measure the voltages to see if they are closer to correct, and check the cathode current of the output tube (and check that the tube isn't red-plating).

Crist Rigott
11-08-2017, 06:48 PM
Nick,
Do you happen to have a Ram p/n that you need. My buddy has a lot of Ram fly backs.

Dave Tilotta
11-09-2017, 07:51 PM
As an FYI, here's what my catalog has.

http://i63.photobucket.com/albums/h123/spectroscopist/MeritCatPage_zpsmlsnvpb5.jpg
http://i63.photobucket.com/albums/h123/spectroscopist/MeritCat002_zpsd7awljel.jpg

miniman82
11-09-2017, 08:36 PM
Crist, Ram number shown in Sams is X-129.

Dave, thank you for the info. I’ll compare it to what I have in the chassis, to see if it makes sense.

Crist Rigott
11-10-2017, 09:25 PM
Thanks Nick. Next time out we'll look for one and let you know.

miniman82
11-11-2017, 02:45 PM
Thanks!

miniman82
12-15-2017, 09:55 PM
Crist, any chance you found a compatible flyback? Unfortunately the Merit one I got from Eric is no good, the outermost part of the HV donut is overheating for some reason.

Crist Rigott
12-17-2017, 09:48 PM
Crist, any chance you found a compatible flyback? Unfortunately the Merit one I got from Eric is no good, the outermost part of the HV donut is overheating for some reason.

Nick,
No joy on the RAM part number. Can you provide the Sylvania part number?

Kevin Kuehn
12-18-2017, 12:52 AM
I've got these 2 Admirals that are apparently close to the HVO 54. The first is new but I only see 3 terminals? No spec sheet either. Second is a pull from a mid 50's Admiral chassis 21A3Z ( Sams 275-2). You can try one or both for postage. If it fixes your problem I'd take a 10 buck donation, or not. :)

https://c1.staticflickr.com/5/4731/27348394769_3cb8e6c474_b.jpg

https://c1.staticflickr.com/5/4601/39094512692_1edd1b153a_b.jpg

https://c1.staticflickr.com/5/4588/39094667742_51a861b768_b.jpg

https://c1.staticflickr.com/5/4638/39094667852_9f305d9e54_b.jpg

miniman82
12-21-2017, 12:28 PM
Kevin, PM sent!

Nick, no joy on the RAM part number. Can you provide the Sylvania part number?


Crist, the Sylvania number listed in Sams is 241-0042 or 241-0037 depending on the chassis. Not sure what difference it makes.

dieseljeep
12-21-2017, 01:00 PM
Crist, any chance you found a compatible flyback? Unfortunately the Merit one I got from Eric is no good, the outermost part of the HV donut is overheating for some reason.
What year is that Sylvania and the chassis number? CRT type?
The Admiral fly shown is for a set with 90 degree sweep and 21AMP4!

Kevin Kuehn
12-21-2017, 01:51 PM
What year is that Sylvania and the chassis number? CRT type?
The Admiral fly shown is for a set with 90 degree sweep and 21AMP4!

I think I see your point.
Both Sylvania part numbers Nick lists cross to Fly 171, vs the Admiral 79C60-2 crosses to Fly 76, and the 79C60-5 to a Fly 77.
Lets make sure the deflection angles match before we make a donation to the USPS.

Kevin Kuehn
12-21-2017, 02:18 PM
I recently picked up a Halolight but unfortunately it won’t make any HV and fails ring test after recap. If anyone has a Merit HVO-54, Thordarson FLY-76, Triad D-49 or other suitable replacement please let me know. Chassis is a 1-533-8.

OK, I looked up your chassis 1-533-8 in Sams 352-16, and it does appear to be a 90 degree deflection CRT. I'm sure you knew that. ;)

I don't know why your OEM fly numbers cross to a Fly 171 in my Thordarson reference, but it could be something as simple as an extra tie-point terminal.

madRad45
12-21-2017, 02:20 PM
the Sylvania number listed in Sams is 241-0042 or 241-0037 depending on the chassis.

Another piece of info... I have the 1969 Merit Replacement Guide cross reference, and both 241-0037 and 241-0042 cross to Merit HVO-124. Maybe the Sams is wrong, or the HVO-54 was the best match at the time and Merit came out with an exact match after the Sams was published. I don't have the catalog to compare the specs.

Kevin Kuehn
12-21-2017, 02:38 PM
https://c1.staticflickr.com/5/4638/25337657988_006e1b941f_z.jpg

https://c1.staticflickr.com/5/4683/38326387825_0790d0504b_z.jpg

Kevin Kuehn
12-21-2017, 02:44 PM
Another piece of info... I have the 1969 Merit Replacement Guide cross reference, and both 241-0037 and 241-0042 cross to Merit HVO-124. Maybe the Sams is wrong, or the HVO-54 was the best match at the time and Merit came out with an exact match after the Sams was published. I don't have the catalog to compare the specs.

Hmm. HVO-124 also crosses to Thor Fly 171. :scratch2:

miniman82
12-21-2017, 03:37 PM
The fly-171 looks closest, even shows the RFC on the plate lead of the HOT.

bgadow
12-21-2017, 10:16 PM
Watching this thread; I have my Halolight on the bench now, no HV, no B-boost, damper is red plating. Hmmm...

miniman82
12-22-2017, 09:49 AM
Your oscillator probably isn’t running, got a scope?

bgadow
12-22-2017, 10:16 PM
Your oscillator probably isn’t running, got a scope?

I do...sometime over the weekend I'll due some probing in that circuit.

miniman82
12-23-2017, 11:13 AM
Is it recapped?

dieseljeep
12-23-2017, 06:02 PM
I do...sometime over the weekend I'll due some probing in that circuit.
With no drive, the horiz output would be the one red plating.
To get the damper red plating, you would almost have to have drive on the HO tube. It still doesn't hurt to scope the drive on the HO. There must be a problem in the boost circuit.
It's been ages since I had to trouble shoot this circuit. :scratch2:

old_coot88
12-23-2017, 09:48 PM
Sounds like a hard short-to-ground somewhere on the cathode side of the damper.

bgadow
12-23-2017, 09:50 PM
There are some paper caps left but I think only in the audio circuit. I haven't hooked up the scope yet but today I dug out my Sencore sweep circuit troubleshooter. HO tube cathode current looked normal & adding drive from the troubleshooter had no effect, though I did notice the damper wasn't glowing like before. Using the troubleshooter's yoke substitution test didn't help; when using its flyback test it points to either a bad fly or something in the load circuit, according to the instructions. Further clues: when I started, the fuse in the yoke circuit was blown. Also, I have replaced the damper, rectifier & HO tube with NOS. Outwardly the fly looks normal. I have also tried hooking it up to my Sel-Son crt subber, which I figured would eliminate the yoke from suspicion. No variance.

bgadow
12-25-2017, 10:06 PM
Success! Now, the rest of the story...

After replacing the filters & vertical/horizontal caps I had decided to power the set up for the first time. Prior to that I happened to peer into the HV cage & noticed that the HO tube had gone to air. This set, per Sams, was built with either a 6CD6 or 6BQ6-mine had the former. No problem-I have thousands of tubes, mostly NOS, & 10' away I'd find a stack of these. But wait...I don't have a single one! How could that be? I coulda sworn...so out comes my trusty Riders tube substitution guide which says 6DN6 or 6EX6. Well, I'm POSITIVE I have some of each...nope! Not a one! I really didn't want to wait for one to be shipped in so I grabbed a thicker tube sub book off the shelf, one published by TAB books. Yep, here it is-says a 6DQ5 also works. Well, that I had-5 NOS ones right at hand. Fast forward.

Later on Christmas Eve, after my wife settled in for her "long winter's nap", I pulled out "GE Essential Characteristics" to study the base diagrams of 6CD6 vs 6DQ5-maybe there's something that's blank on one & a tie point on the other? Well, it turns out they're totally different! Not a sub at all (unless, maybe, if you re-wired the socket-in which case I might as well re-wire to a 6BQ6). Lousy misprint! No wonder the circuit didn't work!

I went to the attic & dug out a box of surplus tubes. I knew for fact that there wouldn't be a 6CD6 in there because, well, I put those tubes there & it just didn't belong. But, there it was, pretty as you please, a NOS Rogers of all things. 10 minutes later & I was staring at a bright raster!

I did some further tweaking today, swapping out some tubes & buttoning up some things. I should have it all back together later in the week. Thanks, guys, as your advice really did work to put me on the right track & helped me learn a thing or two. Now, back to your reguarly scheduled program...uh, thread!

miniman82
01-02-2018, 09:12 AM
Lol, glad it worked out. This Halolight has a 6DN6 in it right now, funny you should mention. Side note, I sent a request to that Ersc place because supposedly they had a good fly on the shelf. Never heard anything back...

Search continues!

miniman82
01-07-2018, 10:07 AM
Mark spotted a Merit HVO-124 replacement on eBay and I bought it, hope it’s good for only $12. lol

miniman82
01-11-2018, 09:14 PM
:banana:


Raster is full and bright, gonna put it back together and enjoy it for a while.


http://videokarma.org/attachment.php?attachmentid=196297&d=1515726725

Crist Rigott
01-11-2018, 10:51 PM
I'm happy for ya!