Official 33609 builder's tread. See 1st page for updates.

Hey Salamonander,

Any chance you could post that original 33609 handbook?  I'm about to resurrect my 33609 project.  I have original 31267 inputs and LO1173 outputs and hopefully some original BA340 on the way.  I need to find some orig 10468s or settle for the best copy I can get.

I rent an original early metal knob 33609 here in L.A. that's just glorious on acoustic instruments and for mid range goodness, the goal is to get close to that.  Interestingly it's not much good on the bus.

Cheers,
Ruairi

Anyone have a spare BA340 board or two kicking around?

Mark
Sharktankpro.com

All links dead on first page... Anyone have them saved somewheres ? ???

Trench Recordings said:

All links dead on first page... Anyone have them saved somewheres ? ???

Click to expand...

BUMP

i'm looking for BA340 parts list as well

any recommendations for transistors hfe ?

1073 preamp needs bc184 with more than 600 hfe, what about this compressor ?

I have all the docs. 
Here is the BA340.
A tip - on my unit I burned out the big transistors initially w/o heatsinks on them. I haven't had a problem once I installed them with heatsinks.

BA340 schematic

Here's a zip file with everything I downloaded at the time, perhaps someone can organize and verify before putting into the tech docs?  I know Igor's BOM is in there but there's another that may or may not be correct.

I've added a .jpg to the end of the zip to get the forum to allow it, just remove that and it should open.

hi guys,

are these pcbs still available? need to get me a couple.
only thing ive found is this:

http://www.diy-racked.com/diy-talk/viewtopic.php?t=18&f=7

dont know if they just do pcbs?

regards

Spence.

dmp said:

I have all the docs. 
Here is the BA340.
A tip - on my unit I burned out the big transistors initially w/o heatsinks on them. I haven't had a problem once I installed them with heatsinks.

Click to expand...

Thanks for the BA340 info.

Do you have a part number for the to-39  heatsinks ? i can't find some that can fit, the space on the board is very limited

Did you use a single heatsink over the five transistors? As on the original BA340

ruairioflaherty said:

Here's a zip file with everything I downloaded at the time, perhaps someone can organize and verify before putting into the tech docs?  I know Igor's BOM is in there but there's another that may or may not be correct.

I've added a .jpg to the end of the zip to get the forum to allow it, just remove that and it should open.

Click to expand...

Thanks for the docs. It seems Igor's bom has some mistakes as well.  I will try to make an updated version

Excellent Beatnik, thanks.

That is exactly what's happening on mine.

Unfortunately because I didn't use the proper pins to mount the BA boards and the last one to go is
unrepairable.  Looking at an original BA340 it looks like just two of the transistors are heat sinked is that what you did on yours DMP? I'm guessing the two final output transistors.

I guess worst case scenario is to design a new board and get a PCB made.

Anyone know a part # or size for the correct pins to mate the BA340 board to the motherboard?

dmp said:

A tip - on my unit I burned out the big transistors initially w/o heatsinks on them. I haven't had a problem once I installed them with heatsinks.

Click to expand...

Do you have a part number for the to-39  heatsinks ? i can't find some that can fit, the space on the board is very limited

Click to expand...

I'm pretty sure I used heatsinks like these on the two output transformers:
532-578305B00 mouser

They just push on the transistors like hats and you can orient them so they don't touch.

nice one thanks dmp

amazing, thank you for the files guys  ;D

Busy building this project and I need to insert the stop  pin for the Elma switches on the limit and comp thresholds - in the build docs pics I see an un-wired elma switch that has the stop pin "0" which gives 24 positions (assuming it hasn't been put to 23 yet?) , but the face plate has 23 Positions for the Limit Threshold and 16 Positions for the Comp threshold - I assume I need to put the pin at "23" and "16" respectively?

- Answer: Realized I need two stopping pins per switch to set the start and end pont

Managed to finally get this build finished today, although the outcome has not been very fun.

The Bypass Board numbering 1-6 is consistent with the main board, but the text "BYP_LINK_MTR" is in the opposite direction on each board, I went with the wrong choice and followed the text instead of the numbering and this resulted in an exploding LM317 on my PSU, replaced the 317 and things seemed to be going OK.

Then R44 (10R) started smoking heavily, TR8 BC461 on the BA340 was very hot too - could not touch it. I replaced R44, checked the voltage across R44 and got a reading of 2V which is still too high. I used the BA340 from the other channel which checked out fine at 260mv, which also worked fine on the problem channel - so there seems to be something wrong with my one BA340.

Both channels of the VU Meter hit hard right and sticks there and none of the controls affect the sound. Only when engaging the "comp in" the sound drops by about 5 db and when selecting comp out it returns back to its level, but none of the controls affect the sound.

Any idea what could be wrong with my one BA340 and why the controls are not affecting the sound and the meters stick hard right? Any help would be highly appreciated! I have read that a few people have had the exact same problem, but they all lead to dead ends with no answer/solution.

I did use the BC214L's but I rearranged the pinout so they go in as CBE, is it a problem to do this?

UPDATE: I figured out that the one trimmer works in the opposite direction to the other? So I managed to get the Voltage down to 200mV but it wont go any higher than 237mV now, I think one of the components on the BA340 must have burnt out when R44 burnt out

UPDATE: Checked the RV1 Trimmer and the resistors, all were within tolerance, logically I thought TR8 BC461 would be the first suspect, changed this out, and Im able to trim to 250-280mV now

Problem would just be with controls not affecting the sound now

I'm still really struggling with this. I have been spending hours searching the thread and scratching my head trying to think of what to do next - I took some measurements from 1 channel and this is the result, perhaps it would help  someone to help me detect where the problems are. Please if anyone could help me or point me in the right direction or help me through this, I would be so so grateful

R14 (10R):  0.265V (Schematic 220-300mV)
R42 (820R): 16.9V (Schematic 17.6V)
TR3: Base: 16.3V (Schematic 17V) // Collector: 4.5V (Schematic 4V)
R9 (100R): 22.8V (Schematic 23.8 )
R2 (10K): 23.4V (Schematic 23.3V)
TR1: - Emitter: 24V Collector: 20.2V Base: 23.42V (schematic 0V) // R61 (240R) - 20.20V (Schematic: 0V)
TR7: Base: 23.9V (schematic: 23.7V) Collector: 0.001V (Schematic 0V)
TR12: 18.13V (Schematic 0.6V) // R28 - 18.13V (schematic 0.6V)
TR11: 1.5V (Schematic 2.5V)
TR10: 17.4 (schematic 17.4), 6.6V (Schematic 6.4V), 7V (Shematic 7V)
TR6: E: 20.5V (Schematic 20.4V), C: 7.3V (schematic 7V)
TR9: 16.9V (Schematic 0.6V)
TR8: 8.7V (Schematic 0V)
R58 (680R): 14.9V (Schematic 9.9V)
TR2: B: 3.5V (Schematic: 4.1V) C: 0.6V (schematic 0.64V) E: 4.2V (Schematic: 4.7V)

At the moment the VU meter is pegged hard right. Audio passes through the unit when engaged and in bypass. When engaged the level is around 6db lower and the controls have little to no effect on the sound.

Bump - Please could anyone help me with this, all this unit is good for at the moment is a door stop and Im really at a loss for what to do  :-\

Finally I finished it!

Here are some photos