EQN build thread

[ruairioflaherty]

Hey Marc,

The inductor is use on the HPF??  I always thought that was in the low frequency eq band.  Anyhow I don't think there's any U.S. distribution for the Carnhill stuff.

I've got a pair of 9043 here but I'm halfway through prototyping an LC mastering eq and I've used one for that.  If you're stuck for one quickly I can send you one of mine from California and you can have Colin send one directly to me? (I guess he'll  replace it for you as you've bought so many).

Are you sure it was the inductor? Seems weird to me...

Cheers,
Ruairi

 

[peter purpose]

Ruairi, HPF is LC based.
Marc.... have you stuck an inductance meter on it? Seems odd that an inductor would fail.

 

[ruairioflaherty]

Hey Peter,

I didn't know that, I need to dig me up a 1084 schematic.  I robbed the 9043 from my kit for an LC eq I'm working on and I can report that it makes for a rather righteous sounding low end when used as a shelf/bell.

Hope all is well back on the mainland..

Cheers,
Ruairi

 

[Marcocet]

Ruairi, HPF is LC based.
Marc.... have you stuck an inductance meter on it? Seems odd that an inductor would fail.

That's why it's the very last thing I checked (after pulling every resistor half way off the board and testing them as well as swapping the grayhill and all of the caps in the HPF section). But I swapped it out and problem solved.

I plan on testing the one I've got thoroughly as soon as I get the time to figure out how. Never tested an inductor before, but it doesn't seem like it should be too complicated.

I'll just order a replacement from Colin. I'm in need of another grayhill for a different project anyway. Thanks everyone!

 

[shabtek]

could be it is "pinned-out" wrong
you could test the resistance against a working one

 

[ruairioflaherty]

Never tested an inductor before, but it doesn't seem like it should be too complicated.

Hey Marc,

I just happen to have the DCR measurements for my pair of 9043 open

Tap 1 - 1.3H - 237 Ohms
Tap 2 - 3H - 373 Ohms
Tap 3 - 7H - 600 Ohms
Tap 4 10H - 738 Ohms

That's give you an idea what's happening at least.

Cheers,
Ruairi

 

[Marcocet]

Thanks!!

 

[jandoste]

Hi Peter,
I didn't find any info for the J1  ??? What I need to do for that?
Thanks,

 

[peter purpose]

A three way .1" header and a jumper, or just stick in a little wire.

 

[jandoste]

so like this...

cheers,

 

[peter purpose]

No

 

[briomusic]

that'll be, cos it's not calibrated 

(RV4!)

 

[jandoste]

that'll be, cos it's not calibrated 

(RV4!)

Great!
Brio,Thanks,
Did it and it works 
Cheers,

 

[jandoste]

I got some hum noise [50-64hz].
any idea ?
Thanks,

 

[peter purpose]

What are you using for power?

 

[jandoste]

What are you using for power?

API Lunchbox.

 

[peter purpose]

Could be a bad dc-dc.... do you have a spare?

 

[jandoste]

Could be a bad dc-dc.... do you have a spare?

Thanks Peter,
Yeah, I tried with other one but it's the same just one unit has the hummmm .
maybe wire connection problem or maybe I soldered R27 with dc because they are so close...

 

[peter purpose]

Did you sort it?

 

[jandoste]

Did you sort it?

Hi Peter,
I got the same problem. I tried with seconde one but same...
maybe it's just the grnd problem?
Thanks,