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Rotary SUT Load Switch

We have not heard from @audi0n00b yet; he said earlier he'd like one board. Let's wait a day or two to see who else might be interested. The cost of the Oshpark board is fine with me.

1/4 watt resistors of all levels of quality are easily available but I've had less luck finding capacitors with incremental values that will fit this board. I found some really expensive silver mica caps from Parts Connexion that have incremental values to fill out the 12 positions in a typical range but can someone point me to some less expensive caps?
 
AvFan said:
...1/4 watt resistors of all levels of quality are easily available but I've had less luck finding capacitors with incremental values that will fit this board. I found some really expensive silver mica caps from Parts Connexion that have incremental values to fill out the 12 positions in a typical range but can someone point me to some less expensive caps?
Click to expand...
You've never said: What range of capacitance do you want (or what specific values)? What type (dielectric) of cap do you want?

C0G MLCC ceramics that fit are in-stock at Mouser from 10pF up to 22,000 pF, with costs from 20¢ up to $6.00.

PP films that fit go from 100pF up to 33,000pF, from 35¢ to 68¢.

PPS films that fit go from 1000pF up to 100,000pF, from 53¢ to $1.50.

So if you want less than 1000pF, C0G is the best bet. 1000 pF and up you've got all 3 types. Ya might have to mix-n-match types to get the values you want, but that's not an issue.

What more do you need?
 
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HalfApt said:
C0G MLCC ceramics that fit are in-stock at Mouser from 10pF up to 22,000 pF, with costs from 20¢ up to $6.00.
Click to expand...

Thanks! I'm kinda of a noob at this stuff so I didn't know about these surface mount caps. I thought they had to be through hole type.
 
 
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Can we buy four boards, or just multiples of three? Bill three, me one.

Unless Athanasios wants to get in.
 
mkane said:
Can we buy four boards, or just multiples of three? Bill three, me one.
Click to expand...
OSHPark in multiples of 3

China shops are all different, some are multiples of 5, some are min 5 then as many more as you want.

With quantities expressed so far, makes no sense to "group buy" from OSHPark, re-mailing just adds to the cost:

AvFan - 3
Athanasios - 3

So from OSHPark you'd have spare(s), someone may want in the future.

I haven't uploaded yet, as there was some uncertainty about what caps fit. So everyone should speak up if you're good with it as-is, or say something if not.

Mocked up some crude eye-candy so ya can see how the switches fit:
Obl-view.jpg
 
HalfApt said:
OSHPark in multiples of 3

China shops are all different, some are multiples of 5, some are min 5 then as many more as you want.

With quantities expressed so far, makes no sense to "group buy" from OSHPark, re-mailing just adds to the cost:

AvFan - 3
Athanasios - 3

So from OSHPark you'd have spare(s), someone may want in the future.

I haven't uploaded yet, as there was some uncertainty about what caps fit. So everyone should speak up if you're good with it as-is, or say something if not.

Mocked up some crude eye-candy so ya can see how the switches fit:
View attachment 2725591
Click to expand...
Athanasios hasn't spoken up yet. I suspect he's working. Myself, I can't see any need for 3, even one would be enough, but I'll do 2 if it helps out with multiples of three. Then again I'm in no hurry. My way of thinking is, I have 4 of the phono stages up and running 3 decks. With this switching I can pair it down to two, one mm, one mc and have 2 as spares.

I'm good as is but, I have a question. Can I use this switching remote, as in next door in the same enclosure, and run wires to the phonostage? The box I'm using has 3 compartments.

ramblin sorry
 
Looks good to me @HalfApt , and this is the design were the pin positions are directly above the board points so headers could be used?

I have 2 v2.x boards and 4 v3.x

You said these won't line up with he V2.x correct?


Athanasios
 
mkane said:
...I'm good as is but, I have a question. Can I use this switching remote, as in next door in the same enclosure, and run wires to the phonostage? The box I'm using has 3 compartments.
Click to expand...
Yes, but ... keeping connecting wires as short as possible is best, that's why it was made to fit directly over the main board load holes. Longer wires running thru the chassis might be prone to pickup radiated noise. I'm not an EE so don't know for sure.
 
AvFan said:
I don't want to assume, but this board can be used with just one switch, correct?
Click to expand...
Correct. Each switch serves both channels. If you don't populate the cap side, you've got resistive loads only. And vice-versa.

BTW, either side can be used for R or C, but the footprints aren't the best match.
 
I would a
HalfApt said:
Yes, but ... keeping connecting wires as short as possible is best, that's why it was made to fit directly over the main board load holes. Longer wires running thru the chassis might be prone to pickup radiated noise. I'm not an EE so don't know for sure.
Click to expand...
What I'll try and do is use shorter standoffs on the phono stage board and relocate the RCA jacks so I can plug in direct.
 
HalfApt said:
Correct. Each switch serves both channels. If you don't populate the cap side, you've got resistive loads only. And vice-versa.

BTW, either side can be used for R or C, but the footprints aren't the best match.
Click to expand...
So one click of the switch get me to let's say 47k/330pf. The next click gets me to 62k/400pf. If I want to change a cap value only on the fly I'll need two Greyhill's, one for resistive load and another for cap value?
 
mkane said:
So one click of the switch get me to let's say 47k/330pf. The next click gets me to 62k/400pf. If I want to change a cap value only on the fly I'll need two Greyhill's, one for resistive load and another for cap value?
Click to expand...
Yes, that's the way it's typically done.

All resistance is done by one switch, all capacitance done by the other switch.

Switch SW1 controls resistance, switching the same resistance to both channels.

Switch SW2 controls capacitance, switching the same capacitance to both channels.

Were you expecting specific pairings of R & C on the same switch?

That's an entirely different board layout, and would still require 2 switches, one for each channel (or a single 4-deck switch vs. two 2-deck switches).
 
mkane said:
Boards ordered. Free shipping:thumbsup:

Thanks HalfApt/AvFan
Click to expand...

Wow, how many did you order?

mkane said:
So one click of the switch get me to let's say 47k/330pf. The next click gets me to 62k/400pf. If I want to change a cap value only on the fly I'll need two Greyhill's, one for resistive load and another for cap value?
Click to expand...

As envisioned the resistance and capacitance loads are separate so dial in what you want for each. Yes, two Grayhill switches for a MM and probably only one for an MC since most MC carts don't care about capacitance. However, you could add another switch and caps if you find a MC cart that is sensitive to different capacitance like Wyn did with his cart.

Since both load caps and resistors are in parallel I don't think there is any reason you couldn't put resistors on the capacitor load switch if you had space and needed more resistance loads (value would be calculated as parallel resistors).

My plan is to have both resistance and capacitance loading switches for my V3.2 MM and one switch for resistance loading of my V3.2 MC. My last switch board will be for my original idea of including a SUT load switch on the primary side of my HM-7s. One of the positions in the MM resistance load switch will be 1Mohm to pair with HM-7 SUT.
 
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