Products > Test Equipment
Teardown - Hitachi V1065
Nidhoeggr:
Hi,
I recently got a Hitachi VC-6045 DSO and I also have the issue with an annoying noise from the PSU board, which true mentioned before. Do you furthermore tried to fix it? It's strange, that you didn't solved it with changing the PSU board. That means the source of the problem is somewhere else?
I located (as far as I could) the sound at the Pulse Amp Transformer T1010 (btw. the schemtatic of the PSU & HV generation board is pretty much the same at the first look in comparison with the V1065) and maybe a bit also comes from the HV transformer, but it's very hard to find the exact spot, where it's coming from.
The supply voltages are fine and the DSO itself work brilliant too, but the noise drives me crazy when I measure over longer periods.
If you guys have any approaches to solve this, I would be very thankfully.
Greetings
Philipp
PS: Sorry for the bad english, I'm from germany ;)
true:
I never figured out the high freq noise issue, as the 1065 now has a freq counter and I'll probably get rid of the 1065A.
This said, I can't find a way to calibrate the frequency counter at all. Don't see anything to adjust on the board that might be related, nor do I see anything in the service manual / schematics... maybe it's some matched components somewhere, sigh... the values do remain pretty close to constant between power-ups and length of time powered up, so maybe I can hack something in somewhere...
grumpydoc:
--- Quote ---This said, I can't find a way to calibrate the frequency counter at all.
--- End quote ---
No, I don't think that there is. Presumably it relies on the CPU clock which is probably fine given the resolution is only 4 digits.
Hydrawerk:
I found a similar scope at school. https://plus.google.com/photos/106264218831814439783/albums/5844454688694290849
true:
--- Quote from: grumpydoc on March 23, 2014, 08:49:00 pm ---
--- Quote ---This said, I can't find a way to calibrate the frequency counter at all.
--- End quote ---
No, I don't think that there is. Presumably it relies on the CPU clock which is probably fine given the resolution is only 4 digits.
--- End quote ---
From what I can see in the circuit description, it depends on the trigger circuit, not the CPU. I am a decent amount off, not just a few digits.
Navigation
[0] Message Index
[#] Next page
[*] Previous page
Go to full version