Transistors for the smoothie.
I tested 10 bf245 (all I had and came up with)
0.747
0.804
0.990
1.078
1.237
1.370
1.403
1.440
1.504
1.626
Would the 1.403 and the 1.440 work as a match?
Thanks,
Ben
1.37 and 1.403 is closer by .004
Jacob
Quote from: jkokura on May 04, 2012, 09:54:17 PM
1.37 and 1.403 is closer by .004
Jacob
Ok, but is this close enough?
At this point, it's your closest match so I'd go with it and not worry about it.
Jacob
Well, Ok. Thanks.
But really the question came about because the instructions say that the transistors much be matched, give a link on how to match them (yours, thanks again) but nowhere do I see any instruction on how close they should be/ need to be/ best to be.
Does a difference of .04 matter at all or is it a big deal?
I think I will try out some different values with what I have to see if I get a big difference with say 1.4 and 1.5, compared to the 1.37 1.4....I'll post what I find.
Ben
FWIW: I matched mine to about .5%, but I also measured about 50 devices. What you have may be fine. You just need to try it out and see if you get good phasing. Socketing the transistors might be a good idea in case you need to get some more closely matched ones.
is there anyone that sells matched jfets for phase circuits? I know guitarpcb used to, but they're always out of stock of em
Quote from: claytushaywood on May 06, 2012, 02:44:47 AM
is there anyone that sells matched jfets for phase circuits? I know guitarpcb used to, but they're always out of stock of em
Yes indeed. GGG sells a matched set of 2N5485's for $3. I built a GGG phase 45 and these work fine:
http://www.generalguitargadgets.com/component/virtuemart/?page=shop.product_details&flypage=shop.flypage&product_id=189&category_id=8
Quote from: pryde on May 06, 2012, 12:19:01 PM
Quote from: claytushaywood on May 06, 2012, 02:44:47 AM
is there anyone that sells matched jfets for phase circuits? I know guitarpcb used to, but they're always out of stock of em
Yes indeed. GGG sells a matched set of 2N5485's for $3. I built a GGG phase 45 and these work fine:
http://www.generalguitargadgets.com/component/virtuemart/?page=shop.product_details&flypage=shop.flypage&product_id=189&category_id=8
GGG states that they are matched within 1/10th of a volt...