Drip STA Level build (now finished !)

[Majestic12]

Looks awesome! Where did you find that huge LED?

Thats a jewel lamp holder (used in many guitar amplifiers). I put in a white LED + resistor and bridge rectifier to make it work with the 6,3AC heater supply.

 

[XAXAU]

Looks awesome! Where did you find that huge LED?

Thats a jewel lamp holder (used in many guitar amplifiers). I put in a white LED + resistor and bridge rectifier to make it work with the 6,3AC heater supply.

Ah, Fender!  8)

 

[skipwave]

Nice work! Looks legit.

Looks awesome! Where did you find that huge LED?

Thats a jewel lamp holder (used in many guitar amplifiers). I put in a white LED + resistor and bridge rectifier to make it work with the 6,3AC heater supply.

No rectifier needed, since the LED is one.

About making time constants variable, as attack and release controls, just do as seen in this Collins 26U schematic:

http://www.waltzingbear.com/Schematics/Misc/Collins_26U1.htm

 

[shabtek]

hey, skipwave!
welcome back

 

[Majestic12]

Nice work! Looks legit.

Looks awesome! Where did you find that huge LED?

Thats a jewel lamp holder (used in many guitar amplifiers). I put in a white LED + resistor and bridge rectifier to make it work with the 6,3AC heater supply.

No rectifier needed, since the LED is one.

About making time constants variable, as attack and release controls, just do as seen in this Collins 26U schematic:

http://www.waltzingbear.com/Schematics/Misc/Collins_26U1.htm

I know that the LED would also work on AC, but it would blink with 25Hz which I find somehow annoying....

 

[skipwave]

I know that the LED would also work on AC, but it would blink with 25Hz which I find somehow annoying....

Wow, you've got sharp eyes, then! I never notice.

Hope my reply didn't come across as flippant, I just wanted to make sure the newbs know LEDs will operate on AC or DC.

I've been slowly, I mean very, very slowly building up a clone of GE Uni-Level / Collins 356E-1:
http://www.waltzingbear.com/Schematics/Misc/Collins_356E-1.htm

 

[skipwave]

hey, skipwave!
welcome back

Thanks dude! I'm making a little time for DIY again. Call it much needed therapy after moving from Chicago to San Francisco to Los Angeles for work.

That power supply PCB you etched for me is still running my Jung-Markell preamps, and I even got around to replacing the power transformer with a torroidal from  Antek. So quiet, clean and detailed, I track guitars and drums through 'em all the time.

 

[Majestic12]

I know that the LED would also work on AC, but it would blink with 25Hz which I find somehow annoying....

Wow, you've got sharp eyes, then! I never notice.

Hope my reply didn't come across as flippant, I just wanted to make sure the newbs know LEDs will operate on AC or DC.

I've been slowly, I mean very, very slowly building up a clone of GE Uni-Level / Collins 356E-1:
http://www.waltzingbear.com/Schematics/Misc/Collins_356E-1.htm

Hehe, maybe you don't notice it because you're on 60Hz mains and your LEDs blink with 30Hz  
I once replaced the lightbulb in a VU meter with only one LED and found it really annoying on AC, so I simply added a second one in reverse

 

[imo]

Majestic,
I am finishing up a Sta-Level as well. It sounds great!
I had a couple of questions, to reference your experience:
Did you build an input pad?
I am using the same transformers as you, and temporarily the 1k pot off of the 200r on the output(i have a T-Pad coming).
I am finding so much gain on this compressor as i have it set up that its almost unusable for me. I have to really pad the preamps coming in.
Do you find the same results as well? All voltages are spot on, and it is working as it should. I have the input pad built for 20dB, and the output so i can go from 10-16dB

I also found that the Sowter output transformer was out of phase from the diagram i found. I ran blue to hot, and grey to cold to get it in phase.
Similar results?
Ian

 

[Majestic12]

Hi,

I don't have an input pad in my unit.
The STA Level has lots of output power and likes to see a 600Ohm load on it's output. When connecting an AD converter with input impedance in the 10K range the levels will probably be too hot.
I have built a 600ohm termination plug (simply two XLR connectors with a 600ohm resistor between hot and cold) that plugs into the output of the Sta Level and will attenuate the signal enough to not overload my converters.

o you find the same results as well? All voltages are spot on, and it is working as it should. I have the input pad built for 20dB, and the output so i can go from 10-16dB

I also found that the Sowter output transformer was out of phase from the diagram i found. I ran blue to hot, and grey to cold to get it in phase.
Similar results?

Hm, I have to check... could be the case but I haven't noticed it yet.

 

[Mellowroni]

Hello Majestic 12!

I was wondering about the ground lift on the input and output. How did you wire this? Did you find it useful?

 

[Majestic12]

The groundlift is just a SPDT switch that either connects pin 1 of the XLRs directly to the case ground or through a 10nF cap with 1M resistor in parallel.
I build it like it is recommended in most drip builds but I don't have to use it at all. Can't even tell if it's turned on or off at the moment

 

[Mellowroni]

Thanks! Forgot to order caps for this from mouser. i'll try without it.

 

[imo]

My Symphony does have a 10k input. I will try a 600r on the output and see if that tames it somewhat.
Thanks
Why didn't you use the input pad?

 

[desol]

Little late but great build Majestic!

A guy I know modified my sta level with fairchild time constants. Definately makes the unit more useable.

Nice work!

 

[Majestic12]

Why didn't you use the input pad?

I didn't have problems with the signal going into the compressor, it's just right. If I would attenuate it I would also get less compression or would have to turn up the inpot knob more.
The output stage is what causes the trouble of overloading most converters.

Little late but great build Majestic!

A guy I know modified my sta level with fairchild time constants. Definately makes the unit more useable.

Nice work!

Yes, at least the release time modification is more than usefull. I don't ever use the unit with its longest release time setting.

 

[Sparqee]

My Drip Sta-Level board has a place for R43 (200K) and it is represented on the schematic but I can't find R43 on the BOM of either the full Drip Sta-Level or the Micro. Anyone have suggestions on what power rating I should use for this?

Thanks.

p.s. Here's the schematic with the location or R43 highlighted and a pic of the board:
vid.firepixie.com/skitch/sta-level-full-...-20140603-133940.jpg
vid.firepixie.com/skitch/iPhoto-20140603-134444.jpg

 

[Bowie]

My Drip Sta-Level board has a place for R43 (200K) and it is represented on the schematic but I can't find R43 on the BOM of either the full Drip Sta-Level or the Micro. Anyone have suggestions on what power rating I should use for this?

Thanks.

p.s. Here's the schematic with the location or R43 highlighted and a pic of the board:
vid.firepixie.com/skitch/sta-level-full-...-20140603-133940.jpg
vid.firepixie.com/skitch/iPhoto-20140603-134444.jpg

The schematic shows 200k.  1/2 watt should be fine.

 

[Sparqee]

My Drip Sta-Level board has a place for R43 (200K) and it is represented on the schematic but I can't find R43 on the BOM of either the full Drip Sta-Level or the Micro. Anyone have suggestions on what power rating I should use for this?

Thanks.

p.s. Here's the schematic with the location or R43 highlighted and a pic of the board:
vid.firepixie.com/skitch/sta-level-full-...-20140603-133940.jpg
vid.firepixie.com/skitch/iPhoto-20140603-134444.jpg

The schematic shows 200k.  1/2 watt should be fine.

Thanks, for that reassurance.  This is my first tube project so I didn't want to make any assumptions about power ratings.

 

[Majestic12]

I also found that the Sowter output transformer was out of phase from the diagram i found. I ran blue to hot, and grey to cold to get it in phase.
Similar results?

Yes, it seems that the transformer is wired out of phase when you follow the drawing from Sowter. My unit was out of phase as well, so I just swapped + and - at the XLR input terminal.

My Drip Sta-Level board has a place for R43 (200K) and it is represented on the schematic but I can't find R43 on the BOM of either the full Drip Sta-Level or the Micro. Anyone have suggestions on what power rating I should use for this?

1/2 or 1/4 watt power rating is just fine for this resistor