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  #16  
Old 03-03-2019, 05:18 PM
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Gleb Gleb is offline
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Quote:
Originally Posted by Hugo barbedo
Take the example of the mullard mustard caps
I believe those Mustards and many others you mentioned are early Polyester types, not paper ones.
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  #17  
Old 03-05-2019, 05:19 PM
Hugo barbedo Hugo barbedo is offline
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hi everyone

i have about 1/3 of the board redone (the part on the right that looks clean)
i have been able to replace all components without removing or unsoldering the board from the chassis.. i just use a round tip iron and bent the tip slightly. so far no traces have been harmed etc..

some resistors are way off, some are marginal and some are spot on. but since they are cheap i am replacing them all
the black paper/film capacitors are a different story, they are all very leaky and off value but the white ones and the grey ones some of them are perfect, but they are also going to the bin.

all the tube sockets so far are fine and i will keep them
the tubes were very very very hard to pull off of the sockets, i was afraid because the board was flexing a lot when wiggling the tubes and pulling them

i have already remade the vertical feedback couplet. that was easy because it has the layout and component values drawed on the back.

the other integrators/couplets/networks have only a part number..putting it on google yields no results. i can identify them on the schematic by their position in the circuit but since my chassis has some variations on the circuitry i can be making the parts with wrong values. can anyone identify the integrators by their part number or point me in the right way please? that would be of a great help
for example one of them is labeled on the board as N3 and has the following code stamped on it: 30-6024-4

WP_20190305_23_02_51_Pro.jpg
WP_20190305_23_03_10_Pro.jpg

best regards
Hugo

Last edited by Hugo barbedo; 03-05-2019 at 08:22 PM.
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  #18  
Old 03-07-2019, 08:05 AM
Hugo barbedo Hugo barbedo is offline
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There is a guy on the antique radio forum by the name of philcoDon that says he has all the diagrams for the integrators by part number but he seems to be inactive since 2015.
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  #19  
Old 03-07-2019, 08:08 AM
WISCOJIM WISCOJIM is offline
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Quote:
Originally Posted by Hugo barbedo View Post
There is a guy on the antique radio forum by the name of philcoDon that says he has all the diagrams for the integrators by part number but he seems to be inactive since 2015.
https://www.legacy.com/obituaries/de...&pid=177032483

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  #20  
Old 03-08-2019, 06:28 AM
Hugo barbedo Hugo barbedo is offline
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i did not know about that i'm sorry
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  #21  
Old 03-08-2019, 06:50 AM
Hugo barbedo Hugo barbedo is offline
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Today i removed the Phase comparer selenium diode to test it
it is 2 diodes wired with a common cathode
it seems shorted in either direction, it read almost zero voltage drop no matter how i test it, even backwards.
can someone tell me a suitable type of modern replacement? maybe 2 fast recovery diodes? 2 general purpose rectifiers?
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  #22  
Old 03-08-2019, 11:15 AM
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AlanInSitges AlanInSitges is offline
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Quote:
Originally Posted by Hugo barbedo View Post
Today i removed the Phase comparer selenium diode to test it
it is 2 diodes wired with a common cathode
it seems shorted in either direction, it read almost zero voltage drop no matter how i test it, even backwards.
can someone tell me a suitable type of modern replacement? maybe 2 fast recovery diodes? 2 general purpose rectifiers?
Schottky diodes will work fine. You can get a common cathode pair in a TO-220 case for about 1€ at Mouser.
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  #23  
Old 03-08-2019, 11:17 AM
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AlanInSitges AlanInSitges is offline
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Quote:
Originally Posted by Hugo barbedo View Post
There is a guy on the antique radio forum by the name of philcoDon that says he has all the diagrams for the integrators by part number but he seems to be inactive since 2015.
Crist Rigotti (here and there) has them all, and makes a replacement set that looks original for 40€ plus shipping. It costs about 55€ all-in to get them to Europe.
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  #24  
Old 03-08-2019, 08:31 PM
Hugo barbedo Hugo barbedo is offline
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Hi alan
thanks. i have some good used dual schotky diodes with common cathode that i can use

i tried searching for the name you gave me but i could not find the guy, can you tell me how to reach him?40€ seems cheap but i want to make the parts myself i just need the layout for my part-numbers maybe he is willing to sell that information to me. I could dip the integrators i am making in epoxy and them paint them orange but i think i will have to troubleshoot alot until the tv works good so for now i will not paint them/dip them.

i have already done another integrator, it is the one on the sync separator. this one has the schematic drawn on the back and it is much more complex than the usual ones on the 10L43 chassis. it uses 8 components and has 7 legs.
the old one had 2 open resistors and one capacitor that measures nothing and somebody bridged a resistor across, it does not seem like a factory modification for sure, looks like some tech bypassed most of the integrator with a 1 meg resistor maybe just to make the set work quickly and dirty



here is the board almost finished
there are a couple of components still not replaced for example the 0,0039uf capacitor across the horizontal osc coil wich is a 10% rated part. i will have to place an order on mouser because i cant find that value locally and the value is crtical on that circuit.
i am also disassembling and cleaning the inside of all the pots. You would be surprised of the amount of crap inside those and just spraying them doesnt work very well. I disassemble them, clean them and bend just a little bit the contact points just to make them press a bit harder against the carbon trace and then i test them.

WP_20190309_02_12_38_Pro.jpg

here is the sync separator network already installed, yes i used some ceramic disk capacitors and i am not ashamed of that,just because i had them in my drawers and i dont think they will be hot enough to cause trouble in this area of the board ,also i dont think a slight drift will affect anything on this circuitry.
i also used some good used resistors that i had in my stash that measured spot on..i am all about convenience, i dont like waiting for parts if i have good reliable ones at hand.
WP_20190309_02_12_44_Pro.jpg

here is the back and its quite "complex"
WP_20190309_02_12_51_Pro.jpg

here is the old part wich is made out of individual components
WP_20190309_02_13_08_Pro.jpg

here is the back with the layout diagram
WP_20190309_02_13_14_Pro.jpg


i think i will do the horizontal integrator that couples the oscillator to the output tube and do a test run on the tv before doing the rest of the integrators.
the horizontal coupling is K7 on the sams for the 10L43 and it has the same part number than the one on my tv so i can do it without fear.
the other three are different part numbers...one of them is on the horizontal AFC area, the other one couples from the sync separator to the vertical osc and the other tiny 3 legged one seems some sort of retrace suppressor


i had already told you that this tv doesnt have the range switch but i found a point on the board labelled "range switch arm" and that point is connected directly to a b+ line
this tv also has a 1uf 50v non polarized cap going from an AGC voltage point to ground.

on most of my german TVs the boost voltage is in the order of 500 to 900volts and we have to use a special type of ac pulse capacitor, i usually go for the wima MKP series, and the manufacturers usually use 1kv or even 1,25kv rated parts.
on this tv the boost voltage is only 400v and the boost reservoir cap was a standard 600v part so i went with a 630v film cap. if that is not advisable please tell me, it is easy to change.

Last edited by Hugo barbedo; 03-08-2019 at 09:21 PM.
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  #25  
Old 03-09-2019, 01:52 AM
Crist Rigott Crist Rigott is offline
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I'm here if you need the Networks. Just pm me.
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  #26  
Old 03-24-2019, 07:43 PM
Hugo barbedo Hugo barbedo is offline
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Thank you very much Crist rigotti for the network information
unfortunately some information on the papers you sent me is not correct when it regards my networks
I was able to find a very very close schematic for my chassis wich even uses the same networks with same part numbers and same component layout... that chassis is the 11n51 and i found the schematic for it on Beitman publication of 1961.
Comparing my old networks with the beitman schematic everything is correct but on the sheet that Crist sent me there are a couple of typos, some incorrect cap values , some missing parts etc.

i have now finished recapping the board

here is the new vertical linearity pot 2watts wirewound and i put a 180ohm resistor in series to act as a stopper to avoid shunting the cathode direclty to ground accidentally if turning the pot all the way to one side. I may have to fit a bigger resistor if that one heats up we will see.
WP_20190325_00_19_46_Pro.jpg

here is an overview of the board with all the new components, you can also see i installed an overkill AFC diode. i used a welding machine double diode, its an ultra fast recovery diode, i used a massive one because it fitted directly in the socket without any modification and it was free
i did not replace the retrace suppressor integrator network yet, i think its not a critical part and i will replace it if i have problems with it
all the others i reproduced and replaced them all because most of them had resistors bridged across them on the bottom of the board indicating bodge repairs from the past
the 0,0039 cpacitor across the horzontal ringing coil was in very sad shape measuring twice the value so i replaced it and since i am going to have to tune the horizontal frequency for sure i went ahead and replaced the 390pf capacitor with a new silver mica 1kv part
WP_20190325_00_20_14_Pro.jpg

here is the back of one of the networks so you can see how i wired them up using solder to make traces
the goal was not to make an exact copy of the old part but to make a sturdy part wich is easily serviceable and modifiable if needed, the legs are made with thick 1.5mm copper so they dont bend and short to the chassis or other components
WP_20190325_00_20_27_Pro.jpg


when i first powered up the set before recapping i had a good raster for some seconds but then i started to see some arcing inside the damper and i shut off the tv thinking it was a bad boost capacitor. I dindt worry about that because it was going to be recapped fully...
Now after recapping the problem remained. arcing inside the damper and blue glow inside the horizontal output. the raster gets darker and breaks down into a zig zag pattern once the arcing starts. removing the top cap of the horiz output and reinserting it live makes the raster come back for a second and then it goes crazy again.....by looking at the horizontal output tube's getter it seems to me that the tube has some air in it. atleast my boxes full of pl36 and pl500 tubes all of them have shiny silver getters and this one is hazy and has some sort of blue colour on the edges.
i dont have any american tubes here so i placed an order for a new damper, horizontal output and a couple of spares for the vertical, audio and others.
i hope its not a problem on the flyback. i checked continuity and resistance of all the windings but that means nothing, nothing looks burnt and i did not see arcing on it and i did not smell any ozone. i think there is a high voltage ceramic disk cap on the horizontal yoke but i am unsure it would cause this and i dont want to mess too much on that area. lets see what happens when the tubes arrive.

meanwhile my flyback is part number 328951 and i am preparing for the worst, if it is bad i need to try and source something that i can fit in...i have rewired and fitted different flybacks on tvs before with sucess but those were german sets that i am used to work with.
when comparing this with other philco flybacks, besides the mechanical fittment this one has a winding separated from the others that goes to both plates of the 6by8 AGC gate/clamp and that winding seems to be absent on most philco schematics i have been looking at

here is the suspicious horiz output
WP_20190325_00_20_50_Pro.jpg

Last edited by Hugo barbedo; 03-24-2019 at 08:36 PM.
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  #27  
Old 03-24-2019, 08:28 PM
Hugo barbedo Hugo barbedo is offline
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Investigating a little bit made me discover that my flyback can be replaced by the thordarson fly 222

https://www.ebay.co.uk/itm/Thordarso...-/401476024832

found this one but the guy doesnt ship to here and he doesnt allow any contact to be made

i also did not have anything better to do so i removed the high voltage rectifier 1b3gt and replaced it with a selenium solid state diode (those white ceramic sticks used in 70's tvs) i used the anode wire and cup from another tv and the thing worked , no arcing or anything...the horizontal output kept glowing blue though...i also was able to draw good arcs maybe 8mm. the horizontal squeal seems a bit off of the usual frequency to my ears, maybe since the set had so many botched up parts they probably detuned the ringing coil preety badly to get it to work.

the plus point is that i have full screen vertical deflection at the first try.

what i need now is to go to bed because here its 2 o'clock in the morning and i need to keep my itchy hands off of the tv until the new tubes arrive!

Last edited by Hugo barbedo; 03-24-2019 at 09:11 PM.
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  #28  
Old 03-25-2019, 05:34 AM
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AlanInSitges AlanInSitges is offline
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That's looking good Hugo! I suspect maybe your set has a different or earlier set of couplates than the ones Crist is making.

If you need to buy the flyback on eBay, you can use http://www.skybox.net/ - it will be easier and cheaper, though it takes a little longer.
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  #29  
Old 03-25-2019, 11:55 AM
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bandersen bandersen is offline
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His set uses a later style of couplates used by Philco in the sets they made right after the Predictas like the 1961 Town and Country. It's fairly easy to unmount the old cylindrical resistors and mount new ones. The caps are ceramic and rarely go bad.
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  #30  
Old 03-25-2019, 03:40 PM
Hugo barbedo Hugo barbedo is offline
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hi bob
hi alan

this is a page from the electronic technician magazine from may 1961
there you can see a 23 inch philco console with 11n56 chassis wich is virtually a 100% match of my chassis including part numbers and layout
1.jpg

that couplate with the replacement resistors looks nice but mine were covered in some sort of goo or resin and some legs had been cut and ressoldered maybe as a diagnostic procedure by some tech so i didnt even remember or bother to try and save them. i did not throw them away though...i always keep the old parts in a bag stapled inside the tvs together with notes that i find relevant about the work done

about the flyback...i managed to get the set working with the selenium solid state HV rectifier stick so the flyback must be good but i will try that method you sugested (skybox) to buy that one on ebay, having a spare will bring me peace of mind.

Last edited by Hugo barbedo; 03-25-2019 at 05:06 PM.
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