PLASMA PBG12201 VU KITS-AS PROMISED!

[Igor]

Yes, the meter outputs on CRM are provides before level control.
You can use hi impedance buffer and hook the meter after the level control.
Please let me know if both channels are working in at least one
(peak or rms) mode.

Check everything, maybe, wrong resistor's value or cap or short on pcb.
I will check, maybe, I was wrong (bad memory),
but the log scale should appear with highlighted segments.

Take the schemo and feed signal to both left and right inputs,
than pass with scope, you will easy find the mistake.

 

[TheGuitarist]

Yeah both left and right are working in average (well 1+2 and 5+6 are jumpered and it works then, but not 3+4 etc).
Could one of the IC's be bad? I just checked all the points and couldn't find any bad components or wrong things. Unfortunately i don't have a scope to test with. It just seems that it isn't getting enough level... i don't understand why though. If you can't think of anything else that could be wrong, i'll try swapping out the ic's soon and if all else fails i dunno... might have to order a new pcb or something... Must have screwed something up somewhere.


Actually come to think of it... i have one resistor that is 27ohms instead of 22... but surely that couldn't completely stop both left and right channels working in average.

 

[sonolink]

I'm looking for PBG12201a aswell. If anyone has leads please let me know...

 

[Igor]

@TheGuitarist:
If both sections RMS are working, than, something wrong after peak detector...
Check: IC3a, IC3d, R-31,35,52,48,36,37,53,54, D4, D8, C16, C20.
Take voltmeter and measure the voltage at pins 1,2,3, of IC3 and respecting second half.
When no signal:
Pin3 0v
Pin2 0v
Pin1 approx. +0.65V
all voltages measured ref. to GND

If all is OK,

Feed signal to input, get approx. 1v at IC4 a/b outs (IC4, pins 1/7),
than, check for approx. 0.6v at pins 3/12 of IC3, same voltages on SV1 4/8.

 

[TheGuitarist]

Ok well i discovered that r35 and r52 are 24.3 ohms instead of kohms... i'm an idiot, obviously i can't read.... changed them out and now it works perfectly! Thanks heaps. Its a beautiful meter and i can't wait to get it in a case.

 

[Igor]

HURRAY!!!!!!!!!!!!!!!

 

[flight]

HI ,

What should be the voltage going to plasma from pin 1 to 8 ??

Without PIC A/D i have respectively from 1 to 8 : ( all DC) measured from general ground
232 v , 65 v , 119 v , 0 , 67 v, 67v ,67v, 228 v

When measured from Ground pin 4 all Dc are half divided ( should it be normal  ? )

When i insert The PIC A/D all dc expect Number 3  fall approximatively by the half .

So Finally i didnt have the plasma illuminated  
What 's wrong ?

Thanks

 

[flight]

Maybe im wrong , but did the display is illuminated without any sound in ?? ( highlighted segments ? always on ? )

 

[sonolink]

Can this circuit be used with the Nixie IN13 and have the same features (VU, PPM, Peak Hold, etc)?
Thanks

 

[Igor]

@flight: please check again wiring, something is wrong here.
Without the input signal, only first segment should be lighted.

 

[Igor]

IN13 will not work here as it is current-versus-lighted length device.
I do have different design VU-meter for IN13's which is cheap
and easier to build than PBG12201-based meter.
IN-13 driver use THAT level detectors, some opamps for every channel, few transistors...etc.
Stabilized 125V source required, but this pcb I have as well.

 

[flight]

@flight: please check again wiring, something is wrong here.
Without the input signal, only first segment should be lighted.

Hey Igor , I have nothing illuminated yet ... ???

1/  Without PIC A/D i have respectively from 1 to 8  going to plasma : ( all DC) measured from general ground
232 v , 65 v , 119 v , 0 , 67 v, 67v ,67v, 228 v
2/ When measured from Ground pin 4 all Dc are half divided ( should it be normal  ? )
3/ When i insert The PIC A/D all dc expect Number 3  fall approximatively by the half .

PS/
I ve scope signal input over pcb , i ve scope it  thru the rectifier stage ( which rectify the sinus to only positif  with an Offset ) then this is eliminated to keep the continus going to buffer and then going to PIC PIN 17 and PIN 18  RiGHT ??
So i didnt suspect the input audio stage . because as you say without sound in i should have first segment be lighted.

Can you tell me a way to test the plasma ??
Also can a Bad Pic could be the problem ?

Thanks

 

[sonolink]

IN13 will not work here as it is current-versus-lighted length device.
I do have different design VU-meter for IN13's which is cheap
and easier to build than PBG12201-based meter.
IN-13 driver use THAT level detectors, some opamps for every channel, few transistors...etc.
Stabilized 125V source required, but this pcb I have as well.

Does it work as VU and as PPM?
Does it have:
-Lin/log scale pin and external input for applications like compressor gain reduction metering?
-Highlighted segments?
-Price and availability of PCBs?

Cheers

 

[Igor]

Hey Igor , I have nothing illuminated yet ... Huh

OK....let me understand what is going here

1/  Without PIC A/D i have respectively from 1 to 8  going to plasma : ( all DC) measured from general ground
232 v , 65 v , 119 v , 0 , 67 v, 67v ,67v, 228 v

Well....

Leave it for now.

Take power supply, measure the output voltages w/o load

There should be:
pin1 +15v
pin2 -15v
pin3 GND
pin4 +250V

At pin4, there can be less (about 230V with load), it is OK, you can adjust it later,
I am OK with 230...240V

Connect power supply to 4-pin Molex connector marked PS on PBG PCB.

Check the voltages are same

7815 (IC3 at power supply board should have heatsink)

There should be correction at power supply pcb if this is the old version
(if you somehow received it?) I marked them all where to put jumper and cut in case of whatever

Only if the voltages measured ref. to pin3 (GND) at PS connector at display board are OK, go next
Check all opamps
BTW, did you installed jumpers properly or switch used?
Pictures wellcome BTW

2/ When measured from Ground pin 4 all Dc are half divided ( should it be normal  ? )

???? What do you mean ground pin4?????????????

PS/
I ve scope signal input over pcb , i ve scope it  thru the rectifier stage ( which rectify the sinus to only positif  with an Offset ) then this is eliminated to keep the continus going to buffer and then going to PIC PIN 17 and PIN 18  RiGHT ??

First, let me know if the power supply is OK
There should be:
pin1 +15v
pin2 -15v
pin3 GND
pin4 +250V

So i didnt suspect the input audio stage . because as you say without sound in i should have first segment be lighted.

Nope

Can you tell me a way to test the plasma ??

Visual test is enough, if it is not broken and does not make sound when you shake it-should be ok
Also can a Bad Pic could be the problem ?
Hm....Everything can be, but please check the power supply connection before

 

[flight]

Thanks Igor !

Take power supply, measure the output voltages w/o load
There should be:
pin1 +15v
pin2 -15v
pin3 GND
pin4 +250V
At pin4, there can be less (about 230V with load), it is OK, you can adjust it later,
I am OK with 230...240V

Connect power supply to 4-pin Molex connector marked PS on PBG PCB.

ALL OK
+15
-16  ( 1V less )
+245

Connect power supply to 4-pin Molex connector marked PS on PBG PCB. Check the voltages are same

All OK

7815 (IC3 at power supply board should have heatsink)

There should be correction at power supply pcb if this is the old version
(if you somehow received it?) I marked them all where to put jumper and cut in case of whatev

Think its Ok , Just something here i used inductor 100UH 3A instead of 1A
and my chinese supplier give me this diode instead of byv95C ( i ll get a byv95C today )

BTW, did you installed jumpers properly or switch used?

Check all opamps

Before inserting them :

IC1                                                          IC2(TL072)                        
PIN 1  0.02  V        PIN 8    0     V                             PIN 1 to 3   0V       PIN 5 to 7  0V
      2  0.02 V              9    0     V                             PIN 4         -16V    PIN 8      +15V
      3  0     V             10    0    V
      4  +15  V            11   -16    V  
   567    0V                12   0  V
                         13 and 14   0.01 V

IC3                                                      IC4 ( PIC )

PIN 1 and  PIN 14   -0.9 V                       PIN 4    5V      PIN 14    5V
Other PIN same as IC1                           PIN 6 TO 11  - 0.03v

What do you mean ground pin4?

Sorry i was talking about PIN 5 going to plasma
which is ground going to plasma via 1M resistance




                                                       

 

[Igor]

OK, I have to take some time when I close to computer at my workplace.
Will do this in short time(day or two).

 

[tomcat]

IN13 will not work here as it is current-versus-lighted length device.
I do have different design VU-meter for IN13's which is cheap
and easier to build than PBG12201-based meter.
IN-13 driver use THAT level detectors, some opamps for every channel, few transistors...etc.
Stabilized 125V source required, but this pcb I have as well.

That would be nice. Have some of this meters and was leaning to the pcbs from papareill.

 

[Igor]

Hi Flight, sorry for "fast" reply, simply had no time to check at work PC...

All seems fine. If there are no mistakes...should work.

All voltages are correct, let's insert op-amps and measure voltages with 1V RMS AC at the input.

 

[flight]

Hi Flight, sorry for "fast" reply, simply had no time to check at work PC...

No Problem Igor  8)

All voltages are correct, let's insert op-amps and measure voltages with 1V RMS AC at the input.

Ok Done here is Result /

                IC1                               IC2
1-3/       0V          8/      -0.25v                1/     -0.92V       5-6/    0V
4/        15V          9-10/     0V                 2- 3 /   0V           7 /    -1V
5-6/      0V           11/       -15v                4/     -15 v         8 /   -15V
7/      -0.26v        12-13-14/  0V


           IC3                                                 IC4 ( PIC )

1/    - 12 V          8 /   0.85V                                       1-2-3 /   OV                10- 11 /    4 V    
2/    - 0.92 V       9 /   0.85V                                           4 /     5V                12-13 /     0 V    
3 /   -0.61 V        10/  0.46 V                                           5 /    0V                 14  /        5 V
4 /    -15 V          11/  15V                                           6-7 /    1,6 V              15-16 /    0 V
5 /     0.5V          12/   0.56V                                          8 /    1,74 V             17 /       0,83 V
6-7/    0.92V        13/   0.86V                                          9 /     0,06V              18 /       0,92 V
                        14 /  -12,06 V

 

[flight]

Igor any bad news there for me ??

thanks
( maybe i can send you back the PIC IC4 if something wrong there )