I keep repeating myself, because almost no one is listening.
Stop using the ground word. It just adds to confusion.
The screen wire is a screen wire. It is not a ground.
Connect the screen wire to Chassis using the lowest impedance connection you can manage.
Well, I'm not an EE so it might be normal for me to confuse some technical terminology. I'll change that configuration then.
Well, I'm not an EE so it might be normal for me to confuse some technical terminology. I'll change that configuration then.
Anything that gives Andrew a brain melt down is ok with me.
Keep up the great work.
Hahahaha
Assembly is finally finished!!
Initial setup and testing on saturday! Regarding the light bulb contraption to power up for the first time, I only have acess to 60W light bulbs, any problem with using one of those?
Air temperatures are around the 30ºC right now so it's a good time to bias it and make sure it handles high room temperatures!
Initial setup and testing on saturday! Regarding the light bulb contraption to power up for the first time, I only have acess to 60W light bulbs, any problem with using one of those?
Air temperatures are around the 30ºC right now so it's a good time to bias it and make sure it handles high room temperatures!
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
So now the troubleshooting begins...
I fired up the amp with the 40W light bulb in the cable and the trimpots are turned all the way counterclockwise. The light bulb doesn't fade out.
I am getting no light on the psu and amp pcb diodes and only 1.2V rail to ground.
I may have made a silly mistake and mounted the diodes reversed polarity, would this prevent the psu rails from raising to full voltage?
I fired up the amp with the 40W light bulb in the cable and the trimpots are turned all the way counterclockwise. The light bulb doesn't fade out.
I am getting no light on the psu and amp pcb diodes and only 1.2V rail to ground.
I may have made a silly mistake and mounted the diodes reversed polarity, would this prevent the psu rails from raising to full voltage?
Did you measure voltage drop across source resistors?
You could also test just the powersupply in isolation (disconnect amp from supply) and retest with light bulb.
I tested it a couple of days ago and go a nice +-33.4VDC on the rails. After that I finished wiring the amplifier pcbs.
So now the troubleshooting begins...
I fired up the amp with the 40W light bulb in the cable and the trimpots are turned all the way counterclockwise. The light bulb doesn't fade out.
Do not rely on the trim pots working this way!
Check and measure.
Then try turning them and watch the result on meter.
Also try 100w bulb.
I'll connect one channel only and power up to see if it is only on one channel or if both are having problems. Any measurements I should make before applying power again?
Here is the datasheet for the trimpots, I believe they increase resistance with clockwise turns. http://www.bitechnologies.com/pdfs/67.pdf
Here is the datasheet for the trimpots, I believe they increase resistance with clockwise turns. http://www.bitechnologies.com/pdfs/67.pdf
I'll connect one channel only and power up to see if it is only on one channel or if both are having problems. Any measurements I should make before applying power again?
Here is the datasheet for the trimpots, I believe they increase resistance with clockwise turns. http://www.bitechnologies.com/pdfs/67.pdf
Don't take ANYTHING for granted!
Be ready for the trim pots working the wrong way, mine did on an F6.
I tested between the legs of the TL431 and they do indeed have the minimum resistance when fully counter clockwise. Left channel is connected to the psu, LED's are emiting light and the light bulb went dimm after a few seconds. It never stoped emitting light. Now on to the right channel.
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