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Electronics => Repair => Topic started by: Spectrum on April 10, 2021, 01:36:34 pm

Title: Tektronix 2335, similar to 2336YA etc...
Post by: Spectrum on April 10, 2021, 01:36:34 pm

Hi, I bought this not working scope which has a BJT on the HV board in short. The transistor is Q161 (2SC2527) one of the tr switching of the  HV trafo. All the other voltages are of correct value (+5 -5 +10 -10 +40 unreg). Someone knows if this board could have some other issue, or some other componenti faulty before give power ?

I found R115 burned but not interrupted, Q115 C 116 and Q116 ore OK.

Title: Re: Tektronix 2335, similar to 2336YA etc...
Post by: bob91343 on April 10, 2021, 07:11:22 pm

I realize English isn't your first language but I really can't understand your message.

Title: Re: Tektronix 2335, similar to 2336YA etc...
Post by: Spectrum on April 12, 2021, 08:26:30 am

I replaced Q161, the scope worked for 10-15 minutes and then the F89 fuse blown again. This happened two times after 10-15 minutes. There is something that absorbs too much after 15 minutes of operation. After replacing the F89, the scope works for 10-15 min. The voltage of 102 V is ok as the others. Could be the HV transformer ?