Low Cost Programmable Decade Resistor for Prototyping Convenience

[sync]

Received mine today. Nine days per air mail from UK to Germany. 

Nice little product! 

Very good accuracy. Set to 123456 ohms and got


I done a little modification. I made solder bridges on the "9" pins. So it doesn't go open circuit when i change the jumpers.

[gerrysweeney]

I done a little modification. I made solder bridges on the "9" pins. So it doesn't go open circuit when i change the jumpers.

I wish I would have done this mod on the next batch but they are already in production Thanks for posting, thats a great mod and one I should have built in from  the off...

Gerry

[Selectech]

My pair came yesterday. Great !

[alank2]

I wish I would have done this mod on the next batch but they are already in production Thanks for posting, thats a great mod and one I should have built in from  the off...

If I were to put my vote in, I would greatly prefer this item without the mod.  I like the idea that if you remove a jumper it goes open instead of assumed "9"...  Without this mod one can always get some extra jumpers and do it that way too...

[mtdoc]

Got mine today. Thanks!   

I wish I would have done this mod on the next batch but they are already in production Thanks for posting, thats a great mod and one I should have built in from  the off...

If I were to put my vote in, I would greatly prefer this item without the mod.  I like the idea that if you remove a jumper it goes open instead of assumed "9"...  Without this mod one can always get some extra jumpers and do it that way too...

I agree. Instead of that mod why not just provide an extra set of jumpers to keep on the 9's.  Also - that way there would be some spares for those of us who tend to lose the little buggers....

[gerrysweeney]

Got mine today. Thanks!   

I wish I would have done this mod on the next batch but they are already in production Thanks for posting, thats a great mod and one I should have built in from  the off...

If I were to put my vote in, I would greatly prefer this item without the mod.  I like the idea that if you remove a jumper it goes open instead of assumed "9"...  Without this mod one can always get some extra jumpers and do it that way too...

I agree. Instead of that mod why not just provide an extra set of jumpers to keep on the 9's.  Also - that way there would be some spares for those of us who tend to lose the little buggers....

Thanks for the comments. From a pure practical point of view, its better with the mod IMHO. If you are working on trimming/tuning live circuits you would generally not want to make the resistor open circuit while changing value, this is why those resistance boxes use make before break switches.  The nice thing about the mod by sync is you can choose to have it or not by simply adding or removing the solder bridge.   The eleventh jumper idea is an interesting one although that could make selecting values error-prone (maybe), but the spare jumpers idea makes sense.  I have asked my assembler to see if they can include the mod at assembly time, not sure if I am too late, we will see. It can always be removed though if thats required.  As always, thanks for the comments.

Gerry

[BillyD]

Received my 2 today. Well packaged and in good time.
Well done on a well thought out and well executed idea, and good luck with the next batch.
Thanks.
Billy.

[gerrysweeney]

Received my 2 today. Well packaged and in good time.
Well done on a well thought out and well executed idea, and good luck with the next batch.
Thanks.
Billy.

Hi Billy,

Thanks very much for your comments, glad you received them OK
 
Gerry

[plesa]

I received it today,  when my coleaques saw it they imediatelly decided to buy their own pieces. Excellent piece of HW.
Just needs to be cleaned from flux residues.

Is there any upcoming version of capacitance decade?

[gerrysweeney]

I received it today,  when my coleaques saw it they imediatelly decided to buy their own pieces. Excellent piece of HW.
Just needs to be cleaned from flux residues.

Is there any upcoming version of capacitance decade?

Hi,

Yes my apologies for the flux residue, I have had a word with my assembler who promises this will be sorted for next time.

I have a 5 decade capacitance one being made as we speak, 100pF to 10uF @ 100V - 10% except for 100pF which is 5%, I should be publishing information about it very soon.

Gerry

[alank2]

I received it today,  when my coleaques saw it they imediatelly decided to buy their own pieces. Excellent piece of HW.
Just needs to be cleaned from flux residues.

Gerry said he thinks his next batch will be cleaned off better.  Just take some 100% isopropyl alcohol to it with a small scrub brush and you can clean it up easily.

Good luck,

Alan

[plesa]

Hi,

Yes my apologies for the flux residue, I have had a word with my assembler who promises this will be sorted for next time.

I have a 5 decade capacitance one being made as we speak, 100pF to 10uF @ 100V - 10% except for 100pF which is 5%, I should be publishing information about it very soon.

Gerry

Splendid!! I will buy few of them for sure.

[tld]

Got one on saturday, ordered earlier in the week through Tindie (not affiliated with either).
I'd really like some places to stick a jumper, but I understand that's probably on the way, so good chance this won't be the last I order.

[ddavidebor]

I received it today,  when my coleaques saw it they imediatelly decided to buy their own pieces. Excellent piece of HW.
Just needs to be cleaned from flux residues.

Is there any upcoming version of capacitance decade?

Hi,

Yes my apologies for the flux residue, I have had a word with my assembler who promises this will be sorted for next time.

I have a 5 decade capacitance one being made as we speak, 100pF to 10uF @ 100V - 10% except for 100pF which is 5%, I should be publishing information about it very soon.

Gerry

another thing to buy   

[gerrysweeney]

It's not a surprise really but here is the first clone! an alternative to mine, pointed out to me this morning by sp6a (thank you)

Search e-bay for: "1R - 9.999999MR Seven Decade Programmable Resistor Board, Step 1R, 1%, 1/4Watt."

eBay Item #161074502921

I should probably be flattered

Gerry

[iloveelectronics]

You should be proud But to be honest this is bound to happen somewhere from China. Funny thing is though they say item location is Hong Kong and yet they don't ship to Hong Kong!  I guess they are doing this to avoid local competition as I wouldn't have seen this item (as HK is excluded from their shipping list) without the exact item number you posted.

It's not a surprise really but here is the first clone! an alternative to mine, pointed out to me this morning by sp6a (thank you)

Search e-bay for: "1R - 9.999999MR Seven Decade Programmable Resistor Board, Step 1R, 1%, 1/4Watt."

eBay Item #161074502921

I should probably be flattered

Gerry

[gerrysweeney]

You should be proud But to be honest this is bound to happen somewhere from China. Funny thing is though they say item location is Hong Kong and yet they don't ship to Hong Kong!  I guess they are doing this to avoid local competition as I wouldn't have seen this item (as HK is excluded from their shipping list) without the exact item number you posted.

Indeed I am, I have not made these to pay the bills, I made these because I wanted to manufacture something using machine assembly and I thought it would be useful for the community.  I love the pricing they have chosen

Maybe I should clone on of their items for fun...

Gerry

[IanJ]

Gerry,

Nothing to worry about, IMO your one has the better layout.

Ian.

[gerrysweeney]

Gerry,

Nothing to worry about, IMO your one has the better layout.

Ian.

Thanks Ian,

Not at all worried - its nice to see someone else thinks its a good idea.

Gerry 

[jasonharper]

This could be made somewhat more compact, using a 2x4 header (which has 10 distinct positions where a jumper can be plugged) and 6 resistors (of two values) per decade.

One downside to this layout is that you cannot short the '9' position to keep the resistance finite when moving a jumper - that would result in an incorrect resistance in some positions due to resistors ending up in parallel.

[gerrysweeney]

This could be made somewhat more compact, using a 2x4 header (which has 10 distinct positions where a jumper can be plugged) and 6 resistors (of two values) per decade.

One downside to this layout is that you cannot short the '9' position to keep the resistance finite when moving a jumper - that would result in an incorrect resistance in some positions due to resistors ending up in parallel.

Nice idea, my concern with that would be usability, it would not be obvious and might be difficult to get a silkscreen legend to make it clear.

Gerry

[tld]

The compact design is neat, but doesn't really fit with how I imagine such a thing typically being used.

Anyone using one would be more than capable of configuring it, but that's not really the goal when you're using it. You don't want to think about it, you want to think about the circuit you're working on.

[jasonharper]

Nice idea, my concern with that would be usability, it would not be obvious and might be difficult to get a silkscreen legend to make it clear.

Good point, here's the clearest/smallest legend I could think of.  The 0/3/6/9 labels could be shared by adjacent decades, which would make the width per decade about 0.4" assuming 0.1" headers.

[gerrysweeney]

Nice idea, my concern with that would be usability, it would not be obvious and might be difficult to get a silkscreen legend to make it clear.

Good point, here's the clearest/smallest legend I could think of.  The 0/3/6/9 labels could be shared by adjacent decades, which would make the width per decade about 0.4" assuming 0.1" headers.

Hi Jason,

Yes thats very compact for sure, quite nice...

Gerry

[ddavidebor]

i've just bought a second one.

how much will it need? i'm still attending the first (it's all ok don't worry!)  O0