I've looked at that one Merlin. Although I can't make sense out of how to implement it. If the pot on the lightspeed just supplies 5v, then all the "stuff" on that board would be for naut. However, there is a really good chance that I am missing something.
What I "think" I need is just a pot with a motor on the back and some form of remote control.
A few of my customers who are lounge lizards have used this RC volume control that I put them onto, you do need all that's there, as it is the power and receiver circuit for the remote the power and driver for the motorized pot, and the relay input switching circuit. The only thing you need to do is to do a bit of surgery to the input/output tracks of the volume control to make it the same as the Lightspeed Attenuator (attached). Also it is not from what I've been told a genuine Alps pot and it is very course in it's action and they seem to think the remote will not last too many years.
Cheers George
Attachments
The carbon film tracks are etched/lazered on a single blank.
The common between input and output is indeed common for both channels.
I don't have the skills necessary to cut the track at common and reattach the lead out wiper, to create two separate tracks.
If you have some other pot that can be hung on the end of the motor then it may be possible to convert this MV02 kit into the driver pot for a Lightspeed.
I do have the pot and gearing mechanism open to take a pic or ten, if you think that modifying the pot is possible.
The operating software in the controller is a bit odd.
The common between input and output is indeed common for both channels.
I don't have the skills necessary to cut the track at common and reattach the lead out wiper, to create two separate tracks.
If you have some other pot that can be hung on the end of the motor then it may be possible to convert this MV02 kit into the driver pot for a Lightspeed.
I do have the pot and gearing mechanism open to take a pic or ten, if you think that modifying the pot is possible.
The operating software in the controller is a bit odd.
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I emailed Pete Millette today to see how much the input impedance is on the Low Mu preamp and he said it is high and matches well with the light speed. So now my next question is: How much difference is there between the lightspeed and lighter note?
You can email me and ask. I dont want to put things like that on George's thread. This thread is specifically about the Lightspeed.
If you are into keeping it simple, you can buy a motorized dual gang Alps pot from Mouser and other sources, (under $20) and then wire it to a remote control box - i.e. wired remote control. Bent Audio also sells raw remote control kits, probably higher quality/better support, (but for more $) than Chinese stuff on Ebay.
http://www.bentaudio.com/index2.html
http://www.bentaudio.com/DLFILES/REM-ALPS-R1.pdf
Looking at the manual, this one also needs the traces cut into/out of the pot cut and then wired manually. Also note it is 50K, not 100K.
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With the Lightspeed Attenuator a 100k dual log will give a nice logarithmic feel to the progression of the volume (gradual from min to 2 o'clock then accelerating to the max). A 50kohm will be very sudden (too quick) down low and not very nice to use.
Cheers George
Cheers George
Will the feel get better with a 250k pot? My chassis needs to gear the volume pot 2:1 so the volume lever will travel 1/2 the distance as the volume pot. That will really make for sudden jumps in volume.
BFNY, thanks for the links. I was looking at my chassis last night and I am now not sure I have the room for any remote controls. I am thinking that I will just built the circuit without remote and go from there.
Very hard to find a dual 250kohm Log Pot, and I think then it would be too insensitive down low to maybe 4o'clock, and then only come on strong way too late around the end and have no control over this.
Cheers George
Cheers George
For those wishing to go the remote path, this looks to be a well sorted one, that uses what looks to be a genuine Alps Dual 100kohm Log motorized pot.
http://www.diyaudio.com/forums/anal...remotely-controlled-motorized-volume-pot.html
Cheers George
http://www.diyaudio.com/forums/anal...remotely-controlled-motorized-volume-pot.html
Cheers George
Suitable volumn pots for LSA
I would like to use two mono pots instead of a dual for better control of channel balance. Can someone recommend a suitable device from Mouser or Digikey. Digikey has KA1041S28-ND, would this be ok ?
Also my current active preamp uses two 10k audio taper volumn pots, can these be used with the LSA ?
I would like to use two mono pots instead of a dual for better control of channel balance. Can someone recommend a suitable device from Mouser or Digikey. Digikey has KA1041S28-ND, would this be ok ?
Also my current active preamp uses two 10k audio taper volumn pots, can these be used with the LSA ?
these Alpha 100K dual log pots are an incredible buy for 2.73 each
see figure E part 313-2420F-100K
http://www.mouser.com/catalog/catalogUSD/645/824.pdf
http://www.mouser.com/catalog/specsheets/TW-700160.pdf
I have one here, tests smooth and works very well, with great resolution.
Then there are the Alps here
http://www.mouser.com/Catalog/catalogusd/645/825.pdf
The 3 in the upper right, dual, 100K, for $11.71
The differences between them are shaft length, and slotted, or D flat.
The 15A taper is typical audio log, plot shown here
http://www.alps.com/products/WebObjects/catalog.woa/E/PDF/Potentiometer/MetalShaft/RK271/RK271.PDF
I'd get this one, the D flat shaft
RK27112A0A16 ALPS Potentiometers
Just remember always stick to the bigger 24mm 100k log pots at 1/2w rating. If you use the smaller 9mm ones they will give trouble after a while.
Cheers George
Cheers George
It was not a mistake that dual section pots were recommended above.
If you go dual mono with the Lightspeed design, you'll still need to buy quantity 2 dual section pots.
There is no way that 2 single section pots will work for the lightspeed implementation of the circuit.
One pot section drives the LEDs for the upper (series R) LEDs, the 2nd section of the dual pot drives the lower LEDs (shunt R). In the standard configuration, each pot section drives both L and R LEDs.
So buy 2 100K dual gang pots for dual mono.
FYI, the power ratings on the pots above (from datasheets) - Alps pots are rated 50mW, the Alpha 250mW.
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