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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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