[jld2112]

Hello all,

I have a Maganovox 51 with no video and no sound (except for the chirping noise)

Model: 51MP392H/17
Chassis: MAG1_AA
Manuf Date: Jan 2005

I recently (last Saturday) replaced both STK392-120 ICs to fix a convergance problem I was having. TV was working fine (and looked great) up until this morning when it suddenly died and is in the state it is now.

I saw thru some eariler searches that a repair kit from another site was availabe for this exact problem but really don't need all the 'extras' included in the kit. I just need a list of parts. This site did not list the actuall parts that were included in this kit.

Is anyone familiar with this problem and have a list of components that need to be tested/replaced ?

Thanks in advance for the help.
JD

 

[lcaillo]

A chirping noise usually indicates that the power supply is being required to produce more current than it is designed to produce and is shutting down. You likely have a short somewhere. Where did you buy the convergence ICs and did you check the resistors? Have you read the first ten posts in the convergence repair thread very carefully?

 

[jld2112]

After reading for almost a week on my original convergence problem, (I never ran across you convergence thread until this evening ... but did take the time to go and read it) I quickly realized the problems with the cheaper IC and went to make the purchase from MCM Electronics.

I did remove all 6 resistors and checked each one and all tested good. Replaced all the parts and everything was fine until today.

Given that I have a new larger DLP on the way this TV was going to be given to my stepson. I was hoping that after I saw a repair kit for this perticular problem I might find the parts list that was in the 'kit' and make a repair for < $50 or so. (For what it's worth the kit is about 70 bucks and the convergence kit was about 60 ... or twice what I paid at MCM)

 

[lcaillo]

I suggest not buying from MCM. Get your parts from B&D or Acme. You don't necessarily need a kit.

So where did you buy the first parts? There is nothing wrong with naming names as long as you are posting FACTS. Understand, however, the parts may not have been bad, and ther could be something else going on. Check those resistors again when you have the chips out of the circuit and the yokes disconnected. the set should run without the ICs as long as the power supplies are up that provide power to the ICs.

 

[jld2112]

I've alwasy had good luck the everything I've bought from MCM and felt comfortable about these IC's being the Sanyo IC's not the cheaper knock-off I'd seen else where after I spoke with a rep on the phone about them (but next time I will go look at B&D or Acme ... I'd never heard of them ... I've always used Newark, MCM, Allied or the like)

The first parts that I bought are the ones that I bought from MCM and those are the only ones that I bought. I did not buy anything from the place that sold the kits. I just mentioned it for an example. (the site was tvrepairkits com and way over priced.)

I can go ahead and pull out the resistors and check them again (alot easier than pulling out the IC's ) but give the age of the set and the new set on the way I don't know that it's worth it to spend too much time going thru the service manual (all 1885 pages of it and troubleshooting it.

If the resistors check out OK again ... What would you, as a SWAG guess, check next if it was you ?

(I did look in it really quick this evening and saw no visiable damage on any of the boards.)

Again ... Thanks for all your help,
JD

 

[lcaillo]

Check to see if the voltages are coming up in the secondary of the power supply. You may need a meter with peak hold feature to catch it if the set is going into shutdown. It may never be starting up also, which would lead me to troubleshoot the PS.