Either I've done something wrong or I don't understand how the isolation board is suppose to work.
I am using the SO1 as an isolator between the Amanero & the BIII which I thought meant the grounds on either side of the board would be isolated, but when I do a continuity test on the ground on either side of the board they are connected?
I assume I have done something wrong?
Any suggestions
I am using the SO1 as an isolator between the Amanero & the BIII which I thought meant the grounds on either side of the board would be isolated, but when I do a continuity test on the ground on either side of the board they are connected?
I assume I have done something wrong?
Any suggestions
Is it as simple as a system ground loop - USB ground to BIII ground? Does the continuity cease if the USB is unplugged.
There is no contunuity apparent on either my SO1, 2 or 3 boards alone, ie bare boards.
Last edited:
Hmm, yes it does stop, but my brain cannot work out why though, I didn't check that because I cannot see how the loop would be formed, I'll have to sleep on it.
Thanks
Must be that the BuffIII/Acko isolator power supplies and the USB are all grounded. My take would be that this is not unusual. Even so, it is the data signals that benefit from isolation, the continuity of grounds depends on the your USB source, if from a PC then I would expect it to be grounded, a laptop may or may not be grounded.
The question is, does it affect the performance? If not sleep well..
The question is, does it affect the performance? If not sleep well..
I finally made time to work out where the loop is. I was powering the test setup with a Kingrex T class amp that I had connected to the AC power via a SMPS.
If I remove the RCA coming from the amp the loop is broken or if I replace the amps SMPS with the Kingrex Transformer based supply the loop is broken.
So the loop is via the SMPS Earth (AC) wire linking to the Negative (DC) in the SMPS and going through the RCA Grnd to the BIII side of the Isolator, and then coming via the the computer earth to the USB Grnd to the Amanero side of the Isolator.
I started all of this looking for a reason that the Infrared Receiver was playing up, they seem very sensitive to grounding. It is working fine now the loop is broken and I suspect If I connect the two star grounds I have (one for Arduino & one for BIII) the infrared problem will also go away if I canot avoid the loop in my main system.
Glad you solved the problem.
Earth and Ground connection definitions should really be made more clear on equipment. As you know Earth and Ground are different things, which cause all sorts of problems when randomly connected together!
I have it working with full sync mode with 22/24 and 45/49 clocks.
Can not get my BuffaloIIIse to lock with 90/98 clocks.
BCK and LRCK look the same on my 'scope with 22/24, 45/49 and 90/98 clocks, but I do not have any equipment to make any sense of the data line.
I am using an Si570 clock board from Ian and manually selecting the frequency.
WIll do some more testing later today.
This is correct:
BCK and LRCK are functions of source sampling frequency(Fs), regardless of MCLK frequencies even if synchronised.
i.e
BCK = 64Fs (32bit data X 2CH)
LRCK = Fs
e.g if playing 192KHz audio then BCK=12.288MHz and LRCK=192KHz.
Please check if this is the case on the scope for 22/24, 45/49 and 90/98MHz MCLKs
Many thanks!
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.