48 Stepped attenuator resistor kit - where buy?

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I.ve got some really nice 50 pole ganged SW's, gurt big heavy duty jobbies which would make decent stepped attenuators, however it'll be a nightmare trying to buy 2 of each R value from Farnell/Digikey etc, especially if I go down the SMD route, as these are usually only available in multiples of 100's on tape.



So does anyone know of a good source of just the resistor kits? All I can find is SW + R kits.


If I've calculated correctly I'll need 100k series 48 X 1.25dB. Still getting my head round this complex subject, forgive any mistakes please.


Andy.
 
If you don't mind dropping a serious amount of cash on those, there are E96 SMD Resistor Kits from Vishay/Dale with 1% Thick Film Resistors, available from 0402 to 1206, pricing starts at around 350 Euros for the 0805 Version from RS Components (excluding taxes). In Germany I can order from RS as a private customer so that would be my choice.

I think you can get so many resistors with the values you actually need for that price and with even higher precision if you so desire. But it sure is easy for prototyping which is what these kits are meant for I guess.
 
Thanks all. I find that RS is a pain to order parts from Jon, they have no where near as many parts as they used to and often after doing a search a lot of parts arn't available.


Thanks for the link shillg.


Way out of my price range kn0ppers, but thanks anyway.


A quick look on Farnell and I see SMD R's are available in 10's, I was hoping to find somewhere where i could buy 48 resistors of the correct value's for a 48 step attenuator. If I end up having to buy 10 of each I guess I can get my cash back by selling kits myself.


Andy.
 
Check Mouser, if I search (for example) for 0805(inch) SMD Resistors with precision lower or equal to 0.1% and a Value of 7,87Ohms I find one model from TE Connectivity that is in stock. It's 1 Euro a piece and the minimum order quantity is 1. It should be the same for most other components.

I am assembling two Neurochrome HP-1 (designed and sold by Forum Member Tom Christiansen - Neurochrome Audio) and while I ordered many of the more common resistors in multiples of 10 or even 100 at a time, for some of the higher precision (and more expensive) ones I ordered quantities lower than 10. It is definitely possible to do that.

I use mostly Mouser and Digikey. Although RS is usually really fast for me in Germany (next day delivery), since they do have a warehouse quite close to where I live. But they have higher minimum order quantities, are often more expensive and have less inventory overall. They also quite heavily restrict what they sell to private customers compared to B2B.
 
I.ve got some really nice 50 pole ganged SW's, gurt big heavy duty jobbies which would make decent stepped attenuators, however it'll be a nightmare trying to buy 2 of each R value from Farnell/Digikey etc, especially if I go down the SMD route, as these are usually only available in multiples of 100's on tape.



So does anyone know of a good source of just the resistor kits? All I can find is SW + R kits.


If I've calculated correctly I'll need 100k series 48 X 1.25dB. Still getting my head round this complex subject, forgive any mistakes please.


Andy.
Try HIFI COLLECTIVE;They have many attenuator kits plus resistors only.I suggest the very good value HOLCO resistors at 25p each.
 
"Check Mouser," Mouser seems to be cheapest.


Thanks for that link and idea russc.


"Try HIFI COLLECTIVE" It was one of the first places I looked, but they only seem to have 24 step attenuators and R kits.


Looking again at the switches I have in more detail they may be best suited to a ladder type attenuator. Each wafer ( two wafers per SW )has 2 x 50 contacts in parallel, see pic.


Thanks for your continuing help and ideas lads, Andy.
 

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"As I have a pair of these" You do? I've not seen anything like em before and thought they were Post Office as was, as you say they are well made and should last 100 years. I would think they're ideal for attenuators as they're make before break.

Get paid on Monday so will follow up the leads and see if I can snaffle some r's. I was thinking of making mine 100k but will see, am in middle of building a valve preamp and havn't settled on the design yet.


Andy.
 
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