Speedball Upgrade. 2 LEDs are off = D1 Diode was not functional. [resolved]

[elgringo81]

Hello there.

I was able to build the crack without problems and all voltage readings were fine and the amp worked like it should.

Tonight I started on the Speedball upgrade and I am experiencing some difficulties.

This is the current status:

Crack: 1U  measures 0V (It used to measure 76V before I started on the speedball upgrade)
Speedball: OA measures 0V

Speedball: LED D1 on A site does not turn on. Other 3 LEDs are glowing fine.
Crack: LED that is connected between Center terminal on socket A and to A8 Does not turn on. The second LED glows fine.

This is what I have done so far,

Resoldered both MJE350's
Resoldered 1U
Resoldered Center Terminal on socket A
Resoldered A8
Double checked that PN2907A are seated correctly (See attached pictures)

I would appreciate any assistance I get with this.


Best Regards,
Gudmundur

 

[elgringo81]

I still cannot figure this out and the weekend is around the corner.
Hope someone can help me with this so I can hook it up to me new 2Qute DAC

Thanks in advance.

 

[Doc B]

With power off, amp unplugged, check the solder pads that the transistors are mounted to (both MJE350 and 2N2907) to make sure that there are no solder bridges between transistor leads. Measure resistance across the LED that doesn't light to make sure that it or the 2N2907 are not shorted. If shorted you will see a very low reading, like 50 ohms or less. Normally that will measure either infinity or over 400 ohms, depending upon the orientation of the test leads with the LED leads. Also make sure your connections from the PC board to the rest of the circuit are good.

 

[elgringo81]

Thanks Doc.

I will follow your advice tomorrow and report back.

 

[Paul Birkeland]

Also, check the DC resistance (with the amp off) between pins A4/5 and pin 6.  If those two are touching, or have started touching since the Speedball was installed, then you'll get 0V where you see it.

Do not do anything to the LED on the tube socket that isn't lighting.  That isn't related.  If it was bad, you would be seeing very high voltage at T1.

Do reheat the center leg of the MJE-350 transistor.  Give it a good 5-10 seconds of heat to be sure the solder is flowing properly. 

I would also suggest taking a photo of the bottom of the PC board and posting it here. 

-PB

 

[elgringo81]

Hello both.

I have been doing my best in following your suggestion and the problem is still unresolved. I have updated new hi-res pictures, see pictures at the fooder of this post.

Doc: I have made sure that there are no bridges between transistor leads, both on MJE350's and 2N2907's.
The resistance across the LED (D1 A side) is infinity.
There rest of the connection on the PC board look fine to my untrained eye


Paul: Pin A4/5 and 6 are not touching.
"Do not do anything to the LED on the tube socket that isn't lighting.  That isn't related.  If it was bad, you would be seeing very high voltage at T1. "
I have not been able to locate T1. Could you please explain further?
I have reheated the center leg of MJE-350 and heated it for 10 sec.
I have spent good time on taking as sharp photos I can in my light conditions. Please see pictures below.         

For some reason I was not able to attach these pictures to this post. They might have been too big (~8mb each) in case there is a size limit, so I have uploaded them to flickr.
https://www.flickr.com/photos/28459414@N08/30732455630/in/dateposted-public/
https://www.flickr.com/photos/28459414@N08/30292764733/in/dateposted-public/
https://www.flickr.com/photos/28459414@N08/30732452860/in/dateposted-public/
https://www.flickr.com/photos/28459414@N08/30292761953/in/dateposted-public/

 

[Deluk]

Note:I haven't done my Speedball upgrade yet, I have the dual small board version of the kit. After looking at your Flickr pictures, am I missing some thing here or are you in fact missing something there? Procedure looks to be that you build up the conversion boards first. Dual or single "small" board and the large board with the heat sinks. No sign of the large board in your pictures. First job when fitting is to start with the "Demolition" as the manual calls it. Although you appear to have removed the 2 small resistors, the big of 22.1k ones are still in place. These have to be removed before fitting the new boards. Even as it stands I can't see a reason why you are firing it up and measuring voltages at this point. Noting that I'm a novice builder, my crack worked perfectly from the start and continues to do so. As always, reading the manual again might be informative. 

 

[elgringo81]

I am just following the manual. Before I install the bigger PCB, I should do some measurements first. To me this also sounds reasonable, since it should simplify the troubleshooting process with fewer components connected.

I have already removed the 22.1KΩ resistors from terminal 1U/2U and 4U/5U. That should be clear on the pictures I have places on the post.

On page 19 in the manual, its time to make some measurements before moving forward. to verify the PCB has been correctly installed.
If the small PCB measures OK I should move on to install the large PCB, starting from page 21.

 

[Deluk]

I think the Speedball manual must have been revised, perhaps then when the 2 small boards were replaced by one. Yes the 2 small resistors are the 22.1 k ones, sorry my mistake, and the big white ones are the 3k ones which should also be removed as part of the demolition. Removing these is on page 18 of my manual. Installation starts on page 19 and goes on to page 25. There is no testing done on these pages. Page 26 says "You're done building!" and after some notes on the next page (26) and a reference picture of the completed chassis (27) the next two pages (28) and into p29 runs through the voltage checks.
Unless there are reasons not to do so, I will follow my instructions without doing any testing. Maybe the BH team had reasons to change/add this bit of interim testing. I don't know, but a comment from them would be interesting.

 

[elgringo81]

I am still struggling with this. And nothing has changed..

Crack: 1U  measures 0V (It used to measure 76V before I started on the speedball upgrade)
Speedball: OA measures 0V

Speedball: LED D1 on A site does not turn on. Other 3 LEDs are glowing fine.
Crack: LED that is connected between Center terminal on socket A and to A8 Does not turn on. The second LED glows fine.

I really hope someone can help me with this because otherwise I have only two choices. This this kit in the garbage or pay for professional assistance.
I am doing this at home and I just got a baby boy so its difficault, if you know what I mean..


I damaged one LED so I will have to order a new one. I live in denmark so it takes forever to get the components from the stated. I will try and see if I can buy it locally.

 

[Deluk]

I bought these as spares. Doc said they were the correct ones. £3.30 + £1.99 to Dk.

http://www.ebay.co.uk/itm/5-X-LED-SUBMIN-RED-Part-HLMP-6000-/351609648339?hash=item51dd9174d3:g:HvYAAOxyd8NSa78D

 

[elgringo81]

Great, thank you. I have places an order for 4x of those.

 

[elgringo81]

I am just wondering if my issue is difficult to solve by those with good experience or if it is just being ignored?



Crack: 1U  measures 0V (It used to measure 76V before I started on the speedball upgrade)
Speedball: OA measures 0V

Speedball: LED D1 on A site does not turn on. Other 3 LEDs are glowing fine.
Crack: LED that is connected between Center terminal on socket A and to A8 Does not turn on. The second LED glows fine.

 

[Rocketman248]

I am just wondering if my issue is difficult to solve by those with good experience or if it is just being ignored?

You have the newer version of the Speedball, whereas a lot of the forum members are experienced with the older version.  Hang in there.  Someone will get you sorted soon. 

 

[elgringo81]

You have the newer version of the Speedball, whereas a lot of the forum members are experienced with the older version.  Hang in there.  Someone will get you sorted soon. 

That is a good point. Have a good weekend,

 

[Deluk]

Great, thank you. I have places an order for 4x of those.

The eBay sale is for 5 off led for £3.30 so if you have ordered 4 you will end up with 20 and it will have cost you about 4 x the money. It confused me too but it does say 5x in the description. Should keep you going for a while.

 

[fullheadofnothing]

What are ALL of the voltages specified in the manual?

 

[Paul Birkeland]

I would also be interested in the voltages at A7 and A8.

You can temporarily disconnect the wires to T1 and T2, then put the 22.1K resistor back in place.  Does this resolve your issue?  (I suspect it will not)

-PB

 

[elgringo81]

What are ALL of the voltages specified in the manual?

The readings are the following, I did them again to respond to you.
I notice an different reading on OA. See below.

OA= -0.2 to -0.4 (Problem) Expected=60-90v
IA= 179,4(OK) Expected=170-270V
B-A/B= 0V (OK) Expected=0V
IB= 179,4V (OK) Expected=170-270V
OB= 74,4 (OK) Expected=60-90V

Source= Page 19 in the Speedball 1.1 Manual

 

[elgringo81]

I would also be interested in the voltages at A7 and A8.

You can temporarily disconnect the wires to T1 and T2, then put the 22.1K resistor back in place.  Does this resolve your issue?  (I suspect it will not)

-PB

I have been back and forth in  the manuals and I cannot terminal T1 and T2. Can you please describe them a little so I can locate them?
Could it be that T1 and T2 do not excist in my build since I have version 1.1 of the Speedball?

"then put the 22.1K resistor back in place"
I believe you mean both 22.1K resistors. I will "rollback" the speedball update and report back.


Here are fresh measurements.

Crack:
A1= -0.3
A2= *
A3= 0
A4= *
A5= *
A6= 0
A7= 55,6
A8= 0 (Nothing is connected to this terminal)


Speedball v1.1 = "Small Circuit Board"
OA= -0.2 to -0.4 (Problem) Expected=60-90v
IA= 179,4(OK) Expected=170-270V
B-A/B= 0V (OK) Expected=0V
IB= 179,4V (OK) Expected=170-270V
OB= 74,4 (OK) Expected=60-90V