[BUILD] New FET/RACK Official Help Thread - Please read first post!

[Echo North]

Just to make sure. I checked my Fuse and it is a 400mA 250V. Would this make a difference when my Voltage is set to the 115?

115/120 is your line voltage. The fuse is rated UP TO 250V so you're good.  We're you able to SAFELY confirm your have line voltage at your IEC?

Mike

 

[bjohnsonaudio]

115/120 is your line voltage. The fuse is rated UP TO 250V so you're good.  We're you able to SAFELY confirm your have line voltage at your IEC?

Mike

Hey Mike. So I looked at the other forum you posted and checked to see my IEC Voltage and I am getting a weird reading. I checked the black connect against ground and got a reading where my multimeter is dancing around 300 range.  When I just turn my multimeter on to the AC reading it sits around 20 when I hold the leads. You are saying to be careful so I don't want to mess around anymore until you let me know your thoughts on this.

 

[Echo North]

Hey Mike. So I looked at the other forum you posted and checked to see my IEC Voltage and I am getting a weird reading. I checked the black connect against ground and got a reading where my multimeter is dancing around 300 range.  When I just turn my multimeter on to the AC reading it sits around 20 when I hold the leads. You are saying to be careful so I don't want to mess around anymore until you let me know your thoughts on this.

You should only be testing for AC.  Anything else, particularly testing resistance, is VERY dangerous and should never be done on the mains.

Not sure what you're doing, but it doesn't add up at all.  At this point we can't even confirm any AC is entering your unit and I'm not sure how to safely guide you through that.

Is your meter self ranging?

Mike

 

[Echo North]

With power on and your meter set to read AC V, you should be able to pop your common probe (black) into a chassis screw hole and probe the "L" tab connector on the IEC. You can still safely get to it with the connector on it.

If you meter has ranges set to whatever range 120V AC is in and you should see about that at the L tab.  If you don't, you have a fuse issue, cable issue, or your meter isn't working.

Mike

 

[Echo North]

Actually you don't even need to turn the unit on, just have it plugged in.

If your fuse is fine, you'll see line voltage at the L tab.

Mike

 

[bjohnsonaudio]

Actually you don't even need to turn the unit on, just have it plugged in.

If your fuse is fine, you'll see line voltage at the L tab.

Mike

Just checked with it plugged in and got a reading of 122 AC V

 

[Echo North]

Just checked with it plugged in and got a reading of 122 AC V

Perfect.  Ok so now we know your fuse is ok.

Now. Pop the power transformer in and power the unit and switch it ON (GR).

With the black DMM probe in a chassis screw hole, check the AC V at the voltage select switch.  There are 6 pads (2 rows of 3) test the one in the lower right, under the word "do" in do not touch.

120 VAC there?

Mike

 

[bjohnsonaudio]

Perfect.  Ok so now we know your fuse is ok.

Now. Pop the power transformer in and power the unit and switch it ON (GR).

With the black DMM probe in a chassis screw hole, check the AC V at the voltage select switch.  There are 6 pads (2 rows of 3) test the one in the lower right, under the word "do" in do not touch.

120 VAC there?

Mike

No I am getting about 38.8

 

[Echo North]

No I am getting about 38.8

Hmmmmm. You have the voltage select switch set to 115?

 

[bjohnsonaudio]

Hmmmmm. You have the voltage select switch set to 115?

Yes. I did it again and got 43.2

 

[Echo North]

That's 38 mV.

So you're not getting anything significant there.

What do you get at that terminal if you disconnect the power transformer from the voltage select board?

Mike

 

[bjohnsonaudio]

That's 38 mV.

So you're not getting anything significant there.

What do you get at that terminal if you disconnect the power transformer from the voltage select board?

Mike

Around 43 mV

 

[bjohnsonaudio]

Around 43 mV

Sorry .7 V

 

[bjohnsonaudio]

Sorry .7 V

I left it on for a second and was reading right above 1 V

 

[Echo North]

I left it on for a second and was reading right above 1 V

With the unit powered and ON and with the power transformer primary disconnected from the voltage select switch.  What is your AC V at the far right pin (looking from the front) of that 7 pin connector on the V select switch.  This is where the red wire would have been connected.

Mike

 

[bjohnsonaudio]

With the unit powered and ON and with the power transformer primary disconnected from the voltage select switch.  What is your AC V at the far right pin (looking from the front) of that 7 pin connector on the V select switch.  This is where the red wire would have been connected.

Mike

1.93 V

 

[Echo North]

1.93 V

I think your meter switch isn't working, so you're never actually powering the unit on.  Double check that soldering and those connections.  If it all looks ok and still doesn't work, shoot us an email.

Mike

 

[bjohnsonaudio]

I think your meter switch isn't working, so you're never actually powering the unit on.  Double check that soldering and those connections.  If it all looks ok and still doesn't work, shoot us an email.

Mike

Mike! You're the man. I just went through and double checked my solder joints, one looked a little funky...I touched it up and I got the +30 and the -10 readings!

 

[Echo North]

Mike! You're the man. I just went through and double checked my solder joints, one looked a little funky...I touched it up and I got the +30 and the -10 readings!

Nice!

 

[Yannic1990]

Hey Guys,

i can´t finish the Calibration for my 1176 Blue. Everything until here worked fine.

I´m stuck Reduction Meter Tracking Adjusment.

I got the 10 DB drop and could calibrate 20:1 but when i switched to 4:1, 8:1 or 12:1
the Meter went crazy.

I then adjusted the null and these Ratios seem to work fine but 20:1 not.

Thanks for your help