View Full Version : Another Predicta thread
Down Under 03-28-2014, 09:30 AM Hi guys,
I've finally had more time to finish restoring a couple of 17 inch Predictas I brought into Australia.
They're almost finished, and the metal gold parts are at the electroplaters. I have them connected to a DVD player with NTSC out, via an NTSC RF modulator. Analogue TV went off ages ago. Powered by a 110V step down isolation transformer (on a 50Hz supply, not 60Hz) and have sound and picture on both of them after the usual recapping etc.
The problem on both TVs is that the picture bounces vertically a bit. Not rolling, it's as though the picture is wobbling on some jelly (jello?) I can't imagine that it's my mains frequency because the vertical oscillator still runs at 60Hz and all incoming power gets converted to DC anyway. The flicker is a bit like the old airport CRT flight schedules, where the text moved back and fourth rythmically.
If anyone has seen this or can point me in the right direction, I'd really appreciate it! The pictures are watchable, but it's slightly annoying.
Also, I'm after the original Philco manuals for the 17 inch Princess or Debutante and the Holiday (my next project) if anyone could please email them to me, or let me know where to find them. The SAMS manuals are great, but it's nice to have both. I luckily found a few pages on Google, but it's not complete.
Cheers and thanks for reading,
Adam
DaveWM 03-28-2014, 10:01 AM a video of the problem would help.
old_coot88 03-28-2014, 10:20 AM Sounds like 50hz ripple on the B+ supply, beating against the 60hz sweep rate.
Down Under 03-28-2014, 05:07 PM Thanks for that,
I can post a link to a video I'll shoot today. I checked for ripple on the three main DC outs, the 275V, the 255V and the 160V, I thought that may have been an issue too. But all is ok! I've replaced all the electros on both TVs, but as always, have to factor in new potentially faulty components. No such "luck" this time!
Cheers,
Adam :)
bandersen 03-28-2014, 05:14 PM Good luck. I'm curious about your electroplating experience. My support arms are all pitted and I'm not sure how to go about restoring them.
Electronic M 03-28-2014, 09:37 PM Could be 50Hz leakage from a tube with a H-K short...
Down Under 03-28-2014, 09:46 PM Hi guys,
I made my first ever web video, I've shared it via Dropbox...
https://www.dropbox.com/sh/wee08ac61if62wd/B6oX5LxF54
Low resolution, about 1.1MB.
Please let me know if you can't open it and I'll try Youtube.
Otherwise, you'll definitely see the shimmer I'm talking about.
I'll keep you all posted about the plating, it will take about 5-6 weeks I was told and cost approx A$300. This includes a lacquering process to protect it. I really hope it goes well, as the firm looked very disorganised! I'd be very upset if they lost anything as I can't easily replace those sorts of parts. They did take inventory though which is a good sign.
I gave them all the metal parts of 3 Predictas in all, a Holiday with roll away stand, the Princess and the Debutante. I couldn't get hold of the missing side end cap for the Princess, so I flattened out a beer bottle cap! Not quite the same, but better than nothing. I'll use a dab of silicone to attach it.
From the Princess, I also removed the aluminium bar the runs across the front grille, as it had pretty much returned to silver. I say this because not all companies will work with aluminium for some reason (low melting point?)
Cheers,
Adam :)
Down Under 03-28-2014, 09:49 PM Could be 50Hz leakage from a tube with a H-K short...
Hmmm... I think Iv'e swapped out all the tubes, but I can check anyway with some NOS tunes I have ready for just such an emergency...
Thanks for the tip!
DaveWM 03-28-2014, 10:24 PM glad you did a video, I would say that is not a HK or any hum related type problem. make sure the yoke pins are clean, the vert height pot is clean, I assume you have replaced the boost cap and all the film caps in the vert circuit.
vert lin pot and bypass cap. oh and let not forget the tube pins, nice and clean.
looks like there is a very subtle flux in the output (not freq) of the vert out tube. somewhat random looking, the last thing I would do is look at the integrators. Or just let it run and see if it clears up on its own.
for hum, ground problems,beat freq problems you would expect to see a very consistant and smooth movement that is precisely timed.
bandersen 03-28-2014, 10:54 PM Weird that both sets have the same issue. Seems like it has to be related to either your power or video source :scratch2:
$300 is an awesome deal for three sets worth of plated parts. I hope it turns out well.
Phil Nelson 03-28-2014, 11:49 PM I'm after the original Philco manualsYou can buy a CD with the Philco manuals on eBay:
http://www.ebay.com/itm/PDF-Scanned-TV-Service-Manuals-on-CD-for-the-Philco-Predicta-also-Bonus-PDF-Ads-/251483362269?pt=Vintage_Electronics_R2&hash=item3a8d9393dd
No affiliation.
Phil Nelson
Phil's Old Radios
http://antiqueradio.org/index.html
Down Under 03-29-2014, 02:16 AM You can buy a CD with the Philco manuals on
Hi Guys,
I've tried him, but he won't post to Australia. One thing I haven't yet asked him is if he will email the files or put them in a shared folder after I pay. I don't really need the disc as the files will end up on the ipad anyway.
All the caps in the vertical circuits have been replaced except the ceramics. I'm also wondering about the couplates, the vertical ones in particular. I'm thinking of building one and subbing it in to test.
The video source can be ruled out, as I used it on my first set without problems. I recently finished an HMV set that looks almost identical to a GE set that Bob was working on, I couldn't believe the similarity. Shown here with a frame of "Tarantula!"
If I don't get a solution to the jiggling, it'll be interesting to see if I still get it when restoring the Holiday. By the way, I've also tried direct video in straight to the 2nd det terminal of the sweep board... no difference sadly. Meanwhile, I'll try your suggestions. Forgot to add: I placed a 470mfd cap in parallel with the main 275V filter cap, also no change. There was no sizable ripple, but I thought I'd try it anyway.
Cheers,
Adam
Down Under 03-29-2014, 03:08 AM Well this is weird. I set the DVD player to NTSC, thinking that would be the most logical. When I set it to PAL, it started rolling like crazy which I expected. But when I adjusted the vertical hold to fix it, I noticed there was no more picture shaking! Now it's as solid as a rock! :D:D
I'm very grateful for all your replies, I'll keep you posted on the plating.
I was originally quoted twice that amount by another company, who, as it turns out, don't plate hollow objects or aluminium. (Wish they'd told me that after I sent numerous pictures to them!)
I'm so happy to have two Predictas working, I'm probably the only one on Australia who does! Can we make it three??
On a different note, is the Sylvania Duelette a hard TV to come by? I'd love to add one of these to the collection.
Cheers and thanks again,
Adam :)
colorfixer 03-29-2014, 04:52 AM I was going to suggest that any transformer inside or near the set would be a cause of this.
One idea: order a small sine-wave inverter from the net, that runs 60hz and power it off a DC power supply running from the 220V mains. The cheaper inverters run quasi-sine which would introduce bars from the harmonic distortion on the power wave form, so avoid these.
kvflyer 03-29-2014, 09:45 AM Hi Adam. My daughter works at MV and lives in Rosanna, VIC. I do come to Australia at least twice a year. Next time, maybe I could bring CD/DVDs over with me. Just a thought.
It would be nice to see a Predicta in Melbourne!
Cheers Mate
Phil Nelson 03-29-2014, 11:24 AM is the Sylvania Duelette a hard TV to come by?Not common around here. I have never seen one in my life, outside of photos.
Phil Nelson
decojoe67 03-29-2014, 12:14 PM Not common around here. I have never seen one in my life, outside of photos.
Phil Nelson
I've seen VERY few good Duelette's up for sale lately. It's a set you really wouldn't want to have shipped by the way. A friend has one that needs a total restoration, and I must say, next to the Predicta's they are one of coolest "space-age" era TV's of them all. They also display a beautiful picture when properly resorted.
Down Under 03-29-2014, 07:41 PM I was going to suggest that any transformer inside or near the set would be a cause of this.
One idea: order a small sine-wave inverter from the net, that runs 60hz and power it off a DC power supply running from the 220V mains. The cheaper inverters run quasi-sine which would introduce bars from the harmonic distortion on the power wave form, so avoid these.
Thanks, I thought of that ages ago and had completely forgotten about it. When I first bought the Predictas, I was thinking of everything I'd have to do to satisfy their working requirements. As it turns out, sending a PAL signal seems to work, although I have no idea why. I would try my PAL RF modulator, but it only outputs on channel zero, so not an option. I bought an NTSC modulator cheaply from Amazon that outputs on Ch 3 or 4. Does the job nicely :yes:
Cheers,
Adam
Down Under 03-29-2014, 07:49 PM Thanks guys,
I had a horrible feeling they were a rarity. But I'll keep my eyes out just in case. As for shipping, it may need to be triple boxed! Fortunately, all 3 Predictas arrived without a scratch, although one had been opened by Customs. I wonder if they thought "who'd buy this junk?" when they saw it?
Its a shame that Australia was so slow to pick up TV technology, the awesome designs of the fifties never made it here.
And to Kvflyer, you're most welcome to come over when you next make the journey, I'm in Bentleigh East, not all that far from Rosanna... about 40-50 mins.
I should at least have the two 17 inchers completed by then.
Cheers,
Adam
Down Under 05-26-2014, 10:31 AM Hi guys,
The sets are finally finished. Both need an alignment, but I don't have the gear or the know how :( But they're watchable.
I also had the cabinets re sprayed in the original beige. Between that and the plating, they look great. Now I'm just starting on my Holiday set.
BTW does anyone have any good pics of the original floor stand for the 17 inch sets? I'd like to buy one, but with shipping costs to Australia to consider and the rarity of these stands, I thought that it might be easier to simply make one. The electroplater has proved their worth, so at least I can get a nice finish on the side bars. The pics that are around don't show a side on view or how the stand is constructed. I'd like to make one as close to factory issue as possible, although I might add castors for a bit of extra height.
Anyway, here's a pic of (possibly) the only working Predictas in AU. I can't seem to add more than one attachment via the iPad, so here's the Princess. I really need to get a better camera than an iPhone.
Cheers,
Adam
maxhifi 05-26-2014, 10:53 AM I just got my hands on a red princess, and I really help it turns out as well as yours did!
bandersen 05-26-2014, 04:06 PM My stand is currently in storage, but I'll try to take some pics next time I stop by. I plan on making a replica someday too. It's just four pieces of square tubular metal for the legs, a painted wood shelf, a metal cross piece to support the TV and some wood trim.
Down Under 05-26-2014, 11:04 PM That would be very much appreciated, Bob. They look simple enough from the pictures I've seen, but there's a few things I still can't quite make out. Measurements are of course the key.
Good luck maxhifi with your red Princess, attention to detail will get you there. One thing I have yet to do is to get the plastic panel with the channel numbers on it re metalised. The process is called vacuum metalising, and it's something I'll look into down the track because the brass border on mine is almost completely gone. Once this has been done (or I find a better panel) it will be nearly perfect.
bandersen 05-31-2014, 11:08 PM There's one on ebay right now with some good photos. http://www.ebay.com/itm/Original-Stand-for-Vintage-PHILCO-Predicta-Television/271507582581
Down Under 06-01-2014, 06:18 AM Hi Bob,
Thanks for that, I'm already watching it! It's interesting if you have a detailed look at it. In particular, have a look at the sloping of the legs.
From the few low res pictures I've seen online of other stands, they're not exactly like an A frame because it looks as though 2 legs meet the floor at a perpendicular, whereas the back pair meet the floor at a small angle.
The one currently listed looks as though one of the legs at the front meets the floor at an angle, whereas the opposite front legs is at right angles. It's almost as though two left or right side frames have been used in this stand, rather than mirror versions as you'd normally expect. Your thoughts on this would be appreciated, because I'm not sure if it's just an illusion or if I'm cracking up! I've also seen pics where the sloping legs face the front, and where they face the back, so I guess it's a matter of personal taste.
If I do win this stand, I'll use it as a template to make another. What I really need is measurements.
Cheers,
Adam
bandersen 06-04-2014, 11:32 PM The stand sold for $409!?! :lmao:
Time to start making reproductions.
bandersen 06-05-2014, 08:56 PM Here are a bunch of photos and measurements of my stand. The legs are 3/4" square 15" long steel stock.
All the wood is poplar painted a satin black with a bronze pinstripe on the lower shelf.
The shelf is 15" long and 11" wide made from an outer frame of 1" stock with a thin board on top.
The metal brackets the support the TV have circular cutouts for the TV cabinet legs. So I''d use you TV as a template to make sure it fits.
https://www.flickr.com/.../700398.../sets/72157645024350042/
Nice to have for sure, but that really are cheaply made.
https://farm3.staticflickr.com/2915/14169512030_6af91d5c38_z.jpg (https://flic.kr/p/nA7sgy) https://farm4.staticflickr.com/3889/14169607377_e51b855635_z.jpg (https://flic.kr/p/nA7WBt) https://farm4.staticflickr.com/3894/14169514870_d05206253c_z.jpg (https://flic.kr/p/nA7t7w)
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