Resistance Check Questions

Caucasian Blackplate said:
If the LED on A8 isn't lighting up, how is the voltage at terminal 1? (It should be high)


Eileen can send you a replacement HLMP-6000 if you burned one, they tend not to short.

-PB

Yup Terminal 1 is now at 140v not the 90 it was earlier in my tests.

I'll see if I can source one locally.
 
If your meter has a diode checker, you can check the LED.  Sometimes the striped end doesn't solder all that well on the center lug of the 9 pin socket.

You won't find the HLMP-6000 in most hobby electronic stores, it is kind of an unusual LED.
 
Caucasian Blackplate said:
If your meter has a diode checker, you can check the LED.  Sometimes the striped end doesn't solder all that well on the center lug of the 9 pin socket.

You won't find the HLMP-6000 in most hobby electronic stores, it is kind of an unusual LED.

Hmm pity! Is there a substitute I could consider that might be more easily sourced without the delay of shipping replacements from the US to NZ?
 
networkn said:
Caucasian Blackplate said:
If your meter has a diode checker, you can check the LED.  Sometimes the striped end doesn't solder all that well on the center lug of the 9 pin socket.

You won't find the HLMP-6000 in most hobby electronic stores, it is kind of an unusual LED.

Hmm pity! Is there a substitute I could consider that might be more easily sourced without the delay of shipping replacements from the US to NZ?

Perhaps for an extra cost BH could sell a $10 kit that contains spares and recommend it to international buyers at the time of their initial purchase, of the most commonly damaged or faulty components (I broke this I believe so I am not suggesting otherwise).

 
networkn said:
Perhaps for an extra cost BH could sell a $10 kit that contains spares and recommend it to international buyers at the time of their initial purchase, of the most commonly damaged or faulty components (I broke this I believe so I am not suggesting otherwise).

We think offering free replacements works a little better, most of the time these things hold up pretty well.

A 475 ohm 1/8 watt resistor will work in place of the HLMP-6000 in the Crack circuit. (470 Ohm is OK too)
 
Caucasian Blackplate said:
networkn said:
Perhaps for an extra cost BH could sell a $10 kit that contains spares and recommend it to international buyers at the time of their initial purchase, of the most commonly damaged or faulty components (I broke this I believe so I am not suggesting otherwise).

We think offering free replacements works a little better, most of the time these things hold up pretty well.

A 475 ohm 1/8 watt resistor will work in place of the HLMP-6000 in the Crack circuit. (470 Ohm is OK too)


Ok what about this?

http://newzealand.rs-online.com/web/p/visible-leds/1934746/

It was suggested by an electronics savvy friend of mine as a possible replacement. LED would suit me better than a resistor as it's nice to be able to see if it's actually working.

Also I can find locally a 470ohm 1/4 watt I presume that isn't close enough?

Also a diode stops current flowing the wrong way too I presume, is that a concern with a resistor in place?
 
The HLMP-6000 is about the last "standard red" LED still in production. Modern red LEDs are brighter and not as deep a red, both of which cause it to drop (slightly) more voltage. You can certainly try another red LED - see if you can find one that is NOT "high-intensity". Monitor the terminal 1 voltage; if it's not too high then what you have will work. Even if it's a bit out of spec, it will work while the replacement wends its way across the ocean ...
 
networkn said:
Well I have a resistor I'll solder tonight and hope like crazy that's the last of the issues.

Hi There!

I have posted my final voltage checks, I am really only wanting to check that 6 and 10 are ok being variable between 15-40mV

1) 90 | 84
2) 170 | 161
3) 0 | 0
4) 170 | 160
5) 90 | 82
6) Wildly going all over the place around 14-40MV
7) 100 | 103.9
0 | 0
9) 100 | 103.9
10) 0 | 14-40MV
11) 0 | 0
12) 0 | 0
13) 170 | 160
14) 0 | 0
15) 185 | 182
20) 0 | 0
21) 206 | 204
a1) 90 | 80
a2) 0 | 0
a3) 1.5 | 1.5
a4) 0 | 0
a5) 0 | 0
a6) 90 | 84
A7) 0 | 0
a8) 1.5 | 1.6
a9) 0 | 0

b1) 90 | 84
b2) 170 | 160
b3) 100 | 104
b4) 90 | 81
b5) 170 | 160
b6) 100 | 104
b7) 0 | 0
b8) 0 | 0

Thanks for all your help.
 
Caucasian Blackplate said:
You're good to go.

14-40mV is 0.014-0.040V, which is nice and low.

Excellent thanks. Kicking myself as there were LED's in the Speedball kit I could have used instead of a resistor until my replacement arrives, however....

I do have a spare 10W10OhmJ Cement Resistor but I can't find any reference to it in the instructions nor parts list unless I am missing something?

 
Hmm well I was very excited to have my first chance to listen today, after nearly 10 days since I completely finished!

Unfortunately something is very not right.

I can only hear from my left channel with my HD650's and there is a horrible buzz in that ear.

Also it appears that my volume was around the wrong way so my measurements were all taken with the device at full tilt, not sure if that should be of concern?

Not even sure where to start looking at this stage. I must admit I thought that when all the voltages were correct and resistance, that meant it was ready!

I am connecting from my PC via USB to an ODAC to the Crack via a 3.5mm to red and white rca and my HD650s are into the 6.5mm jack.
 
Ok well the plot thickens....

With the headphone fully inserted into the jack I can only hear one channel, and it sounds HORRIBLE, pull it out a little I can hear both channels but they aren't anywhere near as good as I imagined, something isn't right I am sure.
 
If you pull the plug out slightly, you sum the channels and present the headphones with a mono signal.

Not having signal in one channel will likely present incorrect voltages, I'd remeasure and double check.

Otherwise, it's a missed solder joint, or a cooked headphone jack.

You can always post pics too, sometimes a miswire is easily spotted.

-PB
 
Hi There!

Startingly this weekend I have finally managed to get back to my crack. I have replied in this thread for historical reference, but if people prefer I can start a new thread.

I haven't touched it since MY last reply, but today I have powered it up to test it again and it's pretty much working fine, EXCEPT now there is a whine in the right hand cup of both my HE-500 and the HD-650's. It's not affected by the following:

1) Removing the Inputs from my DAC, or moving the cables around (twirling them in place)
2) Adjusting Volume.

It's relatively minor, but annoying nonetheless, there is also slight hiss, but I am not certain it's not the source. What is interesting is, that it's not always present.

Where do I start with troubleshooting the whine?
 
networkn said:
Hi There!

Startingly this weekend I have finally managed to get back to my crack. I have replied in this thread for historical reference, but if people prefer I can start a new thread.

I haven't touched it since MY last reply, but today I have powered it up to test it again and it's pretty much working fine, EXCEPT now there is a whine in the right hand cup of both my HE-500 and the HD-650's. It's not affected by the following:

1) Removing the Inputs from my DAC, or moving the cables around (twirling them in place)
2) Adjusting Volume.

It's relatively minor, but annoying nonetheless, there is also slight hiss, but I am not certain it's not the source. What is interesting is, that it's not always present.

Where do I start with troubleshooting the whine?

Interesting. Turned off the Amp and back on again, the HE-500's are fine. Unplugged the He-500 for the HD650's and now instead of a Whine both sides have a significant buzz. Can you not switch headphones like that?

Does it help locate the issue?

Also I am not sure if this is normal but the big Tube is HOT. The metal plate is warmish. My Infrared thermometer says it's 202 degrees Celcius (400F) which seems very hot. The little one shows at 66c (150F).

 
networkn said:
Interesting. Turned off the Amp and back on again, the HE-500's are fine. Unplugged the He-500 for the HD650's and now instead of a Whine both sides have a significant buzz. Can you not switch headphones like that?

Does it help locate the issue?

Also I am not sure if this is normal but the big Tube is HOT. The metal plate is warmish. My Infrared thermometer says it's 202 degrees Celcius (400F) which seems very hot. The little one shows at 66c (150F).

This sure sounds like a loose connection or a bad solder joint that gets jostled around when you plug/unplug headphones.

Tubes do get hot.  If the metal plates on the inside glow red/orange hot, then there's an issue, but otherwise not. 
 
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