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  #76  
Old 12-04-2012, 07:10 AM
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jhalphen jhalphen is offline
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Hi Timmy,

Quote:
i notice using my D-VOM on diode check that one lead on ground and i touch the other to pin 4 on the vert ic the screen jumps like it wants to fill the screen. so it seems to me there is a problem in the sawtooth gen that creates the oscilation
I think you're close: have a real hard look at the 1000pf cap between pins 4 and 5 of the AN5760, maybe it's a trivial as a bad GND on pin 5

To help: closeups of the block diagram + application note schematic of the AN5760.

Last document is a high-zoom of the TR-1010P's schematic showing the AN5760.

Quote:
all voltages on both ics are where they should be with the exception of pin 6 on the vert ic which is 4.8 volts and should be 2 volts maybe because the vert is not under load, working..
Timmy, i don't know what the DC voltage on pin 6 should be but it is the output of the V amp power section driving the deflection coils and the Pana manual specifies 10V peak-to-peak. A VOM reading is meaningless here, the only way to measure this is to see the sawtooth on a Scope (borrow one?)

Hope this helps...

Hi Sandy:
My experience on many of the Panasonic TR-series 1.5" micro-TVs:
TR-1030/1031 always work - built in the second half of the 80s

TR-1010/TR-1020 - before 1984 - a lot of failures, mainly V Scan, no sound, dead or very unsensitive tuners.

Exceptions: TR-1000 nearly always work - better caps!
TR-001, same thing - 1972!

CT-101 shoddy plastics: look at them, they break!
Not really Panny's fault but the people who made the plastics. When new in 1984-1987 they weren't brittle.

Just my 2 Cents....

Best Regards

jhalphen
Paris/France

Last edited by jhalphen; 12-04-2012 at 07:24 AM.
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  #77  
Old 12-04-2012, 11:11 AM
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compucat compucat is offline
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Why is the circuitry on these handheld sets so complex? One would think that given the small size, simpler designs would be easier to build and service plus be more reliable.
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  #78  
Old 12-04-2012, 02:49 PM
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crtfool crtfool is offline
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Quote:
Originally Posted by compucat View Post
Why is the circuitry on these handheld sets so complex? One would think that given the small size, simpler designs would be easier to build and service plus be more reliable.
These were designed and built in the 1980's when SMD components were just getting started - they really were a marvel of engineering, compactness and even simplicity compared to what was previously available. By the time that the TR-1030p series came out, they already reduced the amount of components considerably - and both sets did exactly the same thing. These are 30 years old - comparable technology in today's world make them look very complex. If they redesigned the same set today, it would most likely contain 1 or 2 VLSI chips and a few discreet components plus push-button switches for Power, Volume and Tuning.
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  #79  
Old 12-04-2012, 03:09 PM
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Quote:
Originally Posted by jhalphen View Post
Hi Timmy,



I think you're close: have a real hard look at the 1000pf cap between pins 4 and 5 of the AN5760, maybe it's a trivial as a bad GND on pin 5

To help: closeups of the block diagram + application note schematic of the AN5760.

Last document is a high-zoom of the TR-1010P's schematic showing the AN5760.



Timmy, i don't know what the DC voltage on pin 6 should be but it is the output of the V amp power section driving the deflection coils and the Pana manual specifies 10V peak-to-peak. A VOM reading is meaningless here, the only way to measure this is to see the sawtooth on a Scope (borrow one?)

Hope this helps...

Hi Sandy:
My experience on many of the Panasonic TR-series 1.5" micro-TVs:
TR-1030/1031 always work - built in the second half of the 80s

TR-1010/TR-1020 - before 1984 - a lot of failures, mainly V Scan, no sound, dead or very unsensitive tuners.

Exceptions: TR-1000 nearly always work - better caps!
TR-001, same thing - 1972!

CT-101 shoddy plastics: look at them, they break!
Not really Panny's fault but the people who made the plastics. When new in 1984-1987 they weren't brittle.

Just my 2 Cents....

Best Regards

jhalphen
Paris/France
i forgot to mention when i first got this set the focus diode was bad and its a BB21 and i cant get any info for a replacement so maybe this has something to do with it. i used another diode from a b@w set but much bigger but i got it to fit . it may be wrong for this app i dont know.
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  #80  
Old 12-10-2012, 07:34 AM
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ok, heres what i did. i kind of put that little set in a box for another day or a parts set because i got another 1010p from ebay and this one had the same problem. this one had leaky caps and it took 2 days but it works now after changing 4 caps and placing jumper wires from trace to component. this was extremly difficult having to do this using a magnafier. i notice when the trace corrodes it kind of becomes a resistor so a jumper is then needed. but with the other set it never had any caps that leaked and didnt have to put jumpers so i really dont know to this day what is wrong so i may just hold it for parts. the difference between the 2 sets was that the one i cant seem to fix had the line across the screen but it was not to the other end but the set i fixed the line was from left to right all the way. so the fact that the set where the line didnt make it all the way to the other side kind of tells me something different was going on besides verticle sweep. so now i know 100% whats involved in fixing these and it dont seem to matter if the caps leaked or not or changing all the caps nothing i did on this worked. maybe i have to look for the 101 color this time.
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  #81  
Old 12-10-2012, 02:26 PM
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crtfool crtfool is offline
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I really do not know what went wrong with your first 1010p, but as you can see, a recap and trace repair is what usually fixes these sets. I know that you got good results with only changing the 4 leaky caps, but all the other caps are of the same quality - and with continued use of the TV, they will also fail - they should be replaced with high reliability caps.

If you plan on getting more involved in repairing electronics, you should buy an ESR meter - a decent 1 will cost about $100, but it is well worth it - it will save you a lot of time and aggravation and guess work when it comes to dealing with electrolytic caps.

Either way, GOOD JOB!

Last edited by crtfool; 12-10-2012 at 02:30 PM.
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  #82  
Old 12-18-2012, 09:42 AM
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ok heres the deal on the original tr1010p that i kind of given up on. i learned alot from the 2nd 1010 that i got and fixed and it seems like i missed alot because for some reason when i recapped the the first one i failed to look close at the traces both top and bottom of the board. so now im back on it and of course i found 3 traces that were corroded that i never seen on the top side of the board. so i put jumpers in and now im waiting for another verticle ic because i shorted the one in it. what i learned on the second one was , duh, check the top of the board because i started by taking the back off and went very slow and where ever the solder was discolored i checked the top and bottom and repaired these places and it was fine. the only thing with this set was i could not get the height right and it could have been the height pot resistance was out somewhat but i was able to place a resistor across the verticle coil on the yoke to correct this but i then had just alittle bit missing on the top of the screen so i placed a resistor from one side of the vert yoke coil to ground and now a perfect full screen. i could have pulled the chassis out again to check the height pot but these chassis dont like to be taken in and out as the ribbon is very fragile and besides i didnt have to take anything apart to put these resistors in when i was done i just had to put the back on, nothing else disturbed. and the height control works the way it should as well. so ill see what happens after putting the vert ic in and hope i get verticle sweep this time.
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  #83  
Old 01-07-2013, 12:10 PM
MickM MickM is offline
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Hi;
after reading this thread I went looking for a set.
I found a TR-1030P.
Where can I find info on this?
Are schematics/manuals available?

Thanks
Mick M.
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  #84  
Old 01-08-2013, 11:28 AM
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i think the 1030 circuit is the same as the 1010.
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  #85  
Old 01-08-2013, 11:31 AM
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does anyone have any ideas about lets say any transistor b@w tvs that the set has horizontal but it dont fill the screen and it dont have a width adjustment. any ideas what part of the circuit would be at fault.
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  #86  
Old 01-08-2013, 02:00 PM
MickM MickM is offline
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Hi Timmy;
The Horizontal oscillator drives the horizontal output, which drives the yoke.
The horizontal output also drives the flyback for high voltage.

As sets age component values drift and change.
Resistors increase in value, electrolytics dry up and leak, and also decrease in value, or turn into resistors.

The output stage is a high stress circuit.
The horizontal oscillator is a tuned circuit about 15Khz.
If the oscillator frequency has drifted then the tuned circuit will not be at peak.
This will result in a narrow sweep, as well as low HV.

I would check all R's and C's for correct value and ESR.
Also the yoke could have a shorted turn, or a shorted/leaky cap across it.

To work in this area you need test equipment.
A Scope, DVM, Cap meter, ESR meter, ring tester, HV probe.
You can also lift one lead and tack a replacement part in place to test.

A yahoo search for "tv horizontal circuit":

http://search.yahoo.com/r/_ylt=A0oG7...c/horiz-tv.pdf

Which set are you working on?
Do you have the manual/schematic?

Mick M
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  #87  
Old 01-09-2013, 06:34 AM
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well i checked all resistors and found to be ok and i changed all caps, electrolytics. i have the schematic and it also had corroded traces which i put jumpers. i had a problem getting verticle output but got it now so im left with some of the screen not there and i dont have video but i have sound.
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  #88  
Old 01-09-2013, 03:39 PM
MickM MickM is offline
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Hi;
when you say part of the scrennis not there could you clarify?

Is the whole picuture there but shrunk?
If the picture is offset you may have moved the magnets at the base of the crt.
The yoke should be pushed forward as far as possible.
The magnets look like ears sticking out.

A search for "deflection yoke" will show a picture.
You move the ears to center the picture.

Mick M
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  #89  
Old 01-10-2013, 06:11 AM
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the screen is not full about a quarter inch is missing from the left side and the magnets wont fill it, it helps but thats not the problem. hv is said to be 4500kv so i have 4kv so at this point i dont know why this is happening. i also dont have video maybe this has to do with the screen not full, beams compressed, who knows.
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  #90  
Old 01-18-2013, 12:25 PM
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Contrary to intuition, low HV actually results in a larger raster if everything else is in order.
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