Hitachi Capristor

Beyond · Joined: 23 Dec 2007 Posts: 8

Anyone have a way to check a capristor, I feel that this part is intermittent, and causing me problems in Hitachi TV power supply.

Gravityboots · Joined: 09 Jan 2008 Posts: 38

I have a meter for checking capacitors. Every good TV man keeps one close by at all times. Cost me about 60 US dollars but it's a 3rd limb as far as i'm concerned.

Beyond · Joined: 23 Dec 2007 Posts: 8

I have ESR meter but capristor has spark gap, resistor, and cap, all in one.

vtech · Joined: 08 May 2006 Posts: 1264 Location: USA

There is no reliable way to test a capristor. Just about all you can do is to measure it's resistance with an ohmeter. It is nothing but a high value resistor in parallel with a cap etched in a package. The only ones I ever saw was mainly used as an isolation block for tuner/rf inputs to quench the possible spark.
Used to see them all the time where they'd get popped by lightning and cause snowy picture. You could easily spot the burn mark on one side of the device.

No need to look for one if needed; Just look at the numbers stamped on the device as it denotes the value of it's resistor and capacitor---just get a same value cap & resistor & twist them in parallel together to make a new capristor.

Beyond · Joined: 23 Dec 2007 Posts: 8

Thanks

I will give it a try. The capristor is in a Hitachi TV power area (AP52)I could not get a meter reading, once unsoldered I was able to get a resistance reading. There is a second one in circuit and it seems to be okay.

vtech · Joined: 08 May 2006 Posts: 1264 Location: USA

K, then it is strictly used as protection if/when there may be a spike. otherwise a passive component that has no other effect whatsoever

Curious as to why you think it is intermittent! and exactly what is the problem/symptom that leads you to believe that?

Beyond · Joined: 23 Dec 2007 Posts: 8

I repaired a dead set Hitachi 50ex16B AP52 click only I901 (STRM6511) set came on but protection light came on and -27v led did not light, located that fault (See previous post). Convergence IC's were also replaced 3 x STK 4274 .Set played for a short time than protection led came on all 5 green led's remain on. I do not have a service manual for unit. Video/Audio are good and appear normal. I checked the capristor with meter and was open, after unsoldering it I got a reading of 3.6Meg as marked. Although some remote functions do not work IE: On/Off. Any thoughs

vtech · Joined: 08 May 2006 Posts: 1264 Location: USA

sorry, not familiar with Hitachi's. Perhaps minnie can chime in & give you some pointers. though I can assure you that "capristor" has got nothing to do with your problem.