Voltage and LED trouble

[JacobQ]

Hi everybody,

I completed my 240v Crack kit a couple of days ago and have hit a roadblock with troubleshooting my voltages. I have triple checked all my connections and re-soldered any joins that looked a bit off but I keep coming up with the same problem. All my resistances check out.

If anybody can offer some pointers as to where I should look or what I could try I would be very grateful.

Many Thanks

Jacob

The LED connected to terminal A3 is lit the LED connected to terminal A8 is not

Terminal  -  Given   -  Desired

1  -  124  -  90
7  -  137  -  100
A6  -  123  -  90
A8  -  3.89  - 1.5
B1  -  124  -  90
B3  -  135  -  100

[STURMJ]

I'm stumped from what I can see in the pics everything looks ok.  Check the orientation of the LEDs.  I can't believe no one else has chimed in.

[porcupunctis]

Jacob, start with the two terminal strips on either side of the transformer.  Double check everything to include the orientation of the large electrolytic caps and the diodes.  Re-wet any joint that looks iffy and then re-wet the rest for good measure. 

LED orientation is another good area to check.  This is common because it's easy to turn one around. 

Also, make sure you are counting in the right direction around the sockets.  It looks like you've labeled them and that usually prevents that type of mistake but it is always good to check against the pictures one more time. 

You might also have good luck tracing backwards (electrically) from the connections on either side of the dead diode.

Approach the trouble-shooting with fresh, well-rested eyes and you'll be up and running in no time.

[Paul Joppa]

The non-performing LED will cause the other voltage errors. There's a high probability it is in backwards; next most likely is that it's not soldered well, or is damaged. It's really hard to tell which way is correct; I've checked and been wrong anyhow, many times. If we could get the same LED in a less annoying package, believe me we would!

[JacobQ]

Thank you all for your replies, The problem was with one of the LED's It must have been blown or damaged during assembly. I replaced it using one out of the Speedball kit and it is working fine now. The Crack sounds amazing and as soon as I can get a replacement LED Ill be installing the Speedball. Thanks again for all your help.

- Jacob 

[porcupunctis]

Good to hear that you are up and running.  While you are waiting on the replacement LED, spend some time with the stock Crack.  You'll be amazed at how great it sounds even without the speed-ball upgrade.  Then, you can have that feeling all over again with the upgrade. 

The crack is also a gateway drug for tube rolling.  It's easy and relatively inexpensive since you only need one 12au7 and one 6080/6AS7.  You can spend a whole weekend just reading in this forum what other members have to say about CBS, Mullard, Mazda and Telefunken tubes as well as various power tubes and combinations of the two.  The problem is that once you find one you like, you'll want to buy two more for your Foreplay.

Enjoy the sound.