Author Topic: no trace and toasty resistors mistery  (Read 477 times)

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Offline pitpatTopic starter

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no trace and toasty resistors mistery
« on: May 17, 2020, 10:05:52 am »
I got this hameg 103 scope to be rapired since it died on me while probing the cal. trace. It works in component tester mode but not in scope mode.
After checking every components i found a bf199 transistor that was gone so i replaced it, changed the ac main to 240 ac that fixed the wrong values outgoing from the transf. and recapped all the board but still got no trace.
The only thing suspicious is the big 2w 1k8 resistor that get proper hot with some magic smoke released if neglected.
Scope schematics https://cdn.rohde-schwarz.com/hameg-archive/HM103_englisch.pdf
Some photos of the scope fom an old tread https://www.eevblog.com/forum/testgear/hameg-hm103-problems-repair/
what you guys think?
Thanks to all
 

Offline Gyro

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Re: no trace and toasty resistors mistery
« Reply #1 on: May 17, 2020, 10:56:19 am »
You keep starting new threads about repairing a single piece of equipment (Hameg 103). If you keep starting different threads on the same subject, people will get fed up with cross posting the same information and just give up on you.  :(

https://www.eevblog.com/forum/beginners/oscilloscope-tranformer-extravaganza/

https://www.eevblog.com/forum/beginners/bf199-equivalent/

https://www.eevblog.com/forum/repair/help-with-resurrecting-an-analog-scope-(moved-from-another-section)/

Use one of your existing threads and keep all the information together.
« Last Edit: May 17, 2020, 10:59:11 am by Gyro »
Best Regards, Chris
 
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Offline pitpatTopic starter

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Re: no trace and toasty resistors mistery
« Reply #2 on: May 17, 2020, 11:06:26 am »
You're right I'll try to keep all about this scope in one tread from now on.
« Last Edit: May 17, 2020, 11:07:59 am by pitpat »
 
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