For the ouput section construction the manual says, "After assembly, check that you have very high resistance between the metal tab of both Q9 and Q12 and the heat sink. If you get less than about 60K Ohms (± 20K Ohms) resistance, you MUST correct it."
I did this and one transistor was isolated one was not. I filed the hole and both were isolated and I proceeded with the assembly.
After completing the assembly, I went back through each component and each instruction. When measuring Q9 and Q12, both were not isolated anymore. My question is: did I , by adding more components after this step, re-short out the case to the heatsink. Or, do I need to do something to isolate Q9 and Q12.
Thanks again!
J.B.
Isolation of Q9 and Q12 from heat sink
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Read the manual to see if your question is answered there before posting. Many users will not reply if the answer is already available in the manual.
If your question is about troubleshooting, configuration, or tuning, you MUST include your processor type (MS-I or MS-II) and code version in your post. If your question is about PCB assembly or modifications, you must also include the main board version number (1.01, 2.2 or 3.0).
If you have questions about MS1/Extra or MS2/Extra code configuration or tuning, please post them at www.msextra.com Such questions posted here will be moved to: a temporary MSextra sub-forum, where they will be removed after 7 days
The full forum rules are here: Forum Rules, be sure to read them all regularly.
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Matt Cramer
- Super Squirter
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Re: Isolation of Q9 and Q12 from heat sink
Exactly what resistance did you measure? There is some level of connection between them and ground, so you will see some resistance. If it was in the 100 ohm or less range, though, you've got some trouble...
Re: Isolation of Q9 and Q12 from heat sink
300 ohms wi + on the tab - on the sink.(each)
315 ohms wi - on the tab + on the sink. (each)
315 ohms wi - on the tab + on the sink. (each)