universal bridged-t attenuator boards

Interested to get pimped with a bridged T, who are you refering too?

eskimo said:

Interested to get pimped with a bridged T, who are you refering too?

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Since you asked, I will pimp it up.

Here is a link the t-pads on my site.

Here is a link the t-pads on Hairball Audios site.

We both resemble the picture there but when I smile...my full grill shows

Cheers, Jeff

eskimo said:

Interested to get pimped with a bridged T, who are you refering too?

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Looks like a guy I tracked a few sessions.. all show, was straight no go...  Used to flash like $200 in ones with a hundred on the outside. I coined the term "Pimping inda Budget" when I referred to him and our dealings with him. He was so cheap it wasn't even funny. One night one of the other guys went out with him and came back telling us about how he was refilling high $ bottles with boones farm and other cheap drinks and passing it off to the ladies...


Pimp on Classic API... your at the DIY builders ball!

i really like the lorlin pcb idea, for what its worth.

I made an attenuator PCB for an 1176.  It was designed with a dual purpose in mind.  It can be a T-attenuator per NYDave's schematic, or a means to terminate a nice Grayhill switch to 2x 12 pin Molex connectors (for the 1272 hotrod build).  The switch model number written into the board is a shorting Grayhill with 2 decks, 12 positions, 360 deg rotation and adjustable stop.

The pcb is sized for the Express PCB Miniboard service.

Nice work; have you ordered prototypes?

Yeah, they're in use in both my 1176 and 1272 Hotrod and they work quite well.  I haven't made any for sale because the Clarostat conductive plastic attenuators became available for about as much money as the Grayhill switch cost.

Also, my friend and I are considering making a board for a 6 pos H-pad to place in front a fixed gain racked mic pre.

I held off from commenting about the switch price.  Too bad there's not a cheaper way.  Still, great for repeatability and precision when needed. 

Sure wish those schematics were still around somewhere...

No much schematics needed, go on google for bridged t attenuator and you'll find something for sure, the boards are other thing, but hard to get boards from a 6yo project... not much needed anyway for a board, you could build them with resistors directly on the switch.

JS

bluesbaz said:

Sure wish those schematics were still around somewhere...

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It might be worth private messaging “andre tchmil”. I know he was working on a similar project.

Andre said:

Also, my friend and I are considering making a board for a 6 pos H-pad to place in front a fixed gain racked mic pre.

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H-pad is definitely NOT the best choice for mic inputs. H-pads are necessary when input and output impedances must be equal, for cascading purposes.
But in the case of mic pads, the input impedance should be about 10x the output impedance; that is why, in particular, a mic pad with less than 20dB attenuation cannot be designed optimally.
This is particularly important with xfmr inputs, transformerless are much more tolerant.
Best structure for mic pads is U-pad. They can be cascaded, but don't expect two 10dB pads to combine at 20dB.