Farnell have them .... 20 quid min charge if I buy through the website and 30 quid to use the phone order line ..... No thanks . Digikey has no minimum charge and 12 pound shipping .... I was going to wait and see if I need to replace anything else before I ordered.
Im off work waiting for a double hip replacement ... every penny counts
readings ...
Im off work waiting for a double hip replacement ... every penny counts
readings ...
Attachments
Hips, ouch.
I see the 62v, do you have 31 to ground at the amp boards?
I don't know what a quid is.
I see the 62v, do you have 31 to ground at the amp boards?
I don't know what a quid is.
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Right Channel
25 V + to Ground = 30.35
25 V - to Ground = 32.35
Left Channel
25 V + to ground = 32.26
25 V - to ground = 30.45
Rich
25 V + to Ground = 30.35
25 V - to Ground = 32.35
Left Channel
25 V + to ground = 32.26
25 V - to ground = 30.45
Rich
OK, check to see if your offset is plus or minus so we can tell which half of the amps aren't working. It looks like it will be minus.
I think you misunderstood. We are looking for DC at the output of each amp where a spkr would be hooked up, that is the offset. The amp is supposed to be balanced so that there is only millivolts at the spkr hookup. If one set of fets is turned off, as you have, the offset will be very high.
ok ,
right amp reads 28.79 v dc
left amp reads 30.69 v dc
if you would find this easier by phone I would gladly pay for the call ... just PM me your number if you want ..
Rich
right amp reads 28.79 v dc
left amp reads 30.69 v dc
if you would find this easier by phone I would gladly pay for the call ... just PM me your number if you want ..
Rich
I think I see your problem. On the amp board pic in a previous post it seems you have the 2 9610s bolted together with no insulation between them. That bypasses the resistor that supplies voltage to the fet gates. They must be electrically isolated from each other. The tabs on the 9610s are hooked to the drains internally.
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lol
I have a silpad between them ,but I used a steel 3mm bolt🙄 ... I will change it
now and get back to you .... Nylon should be ok ?
I have a silpad between them ,but I used a steel 3mm bolt🙄 ... I will change it
now and get back to you .... Nylon should be ok ?
Yep, I bet that's it, nylon is fine. It's not absolutely necessary to connect them thermally either, I've never done it and my offset drift has always been minimal.
yes, in the UK, I have found that Power resistors are far cheaper.
I bought a 1000 pack of 5W 20r to allow assembly of a variety of dummy loads and to build up soft start resistances.
the To220 package has an exposed tab for the bolted connection.
Most of the other packages have an insulated bolted connection, eg. To126, To247, To264.
The back face of all of these have a heatsink interface that is electrically connected to the middle pin of the BJT and FET.
great ..... 30 @ 1 and 9 @ the other ! its gonna be a long night
I am getting readings that were previously dead prior to removing the steel insulation ...
Ill never live that down ....
Rich
I am getting readings that were previously dead prior to removing the steel insulation ...
Ill never live that down ....
Rich
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