I'll fix the library to use fatter pads, that'll be more consistent and prevent having to do this again next time.
V1 was 0.8" x 2" as per Bajaman's directions. V2 is 0.8" x 1.8" because I squeezed it down a little to save space.
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Stingray aftermarket 2 band pre
- Thread starter blmeier7
- Start date
I'll fix the library to use fatter pads, that'll be more consistent and prevent having to do this again next time.
V1 was 0.8" x 2" as per Bajaman's directions. V2 is 0.8" x 1.8" because I squeezed it down a little to save space.
That's pretty sweet. I wonder if they are making the natural finished one? I like the concept of those mute bridges but you can get the same thing by folding up a little foam rubber and shoving it in under the strings. I tell you what, they really make a great bridge. If there's one thing I would buy from EB it would be one of those bridges.
Sent out an update PM to everyone I have listed as wanting a board. If you're wanting a board and didn't get a PM, I probably missed you. Apologies and please PM me a reminder.
Update:
Work's been doing the "we fired loads of people and want those of you who are left to work 12 hour days unless you want it to happen again" thing this week
However I got an hour this evening to do a quick run of the fatter artwork and quickly drill and solder a test board to check everything fits right.
There are a couple of minor tweaks needed, but here we go:
(A little ugly, I know, but it's just a tester and I was rushing).
All being well, I'll etch a full batch tomorrow and send out PMs.
Work's been doing the "we fired loads of people and want those of you who are left to work 12 hour days unless you want it to happen again" thing this week
However I got an hour this evening to do a quick run of the fatter artwork and quickly drill and solder a test board to check everything fits right.There are a couple of minor tweaks needed, but here we go:
(A little ugly, I know, but it's just a tester and I was rushing).
All being well, I'll etch a full batch tomorrow and send out PMs.
Update:
Work's been doing the "we fired loads of people and want those of you who are left to work 12 hour days unless you want it to happen again" thing this week
There are a couple of minor tweaks needed, but here we go:
(A little ugly, I know, but it's just a tester and I was rushing).
All being well, I'll etch a full batch tomorrow and send out PMs.
looks great!
I've had my share of ***hole company owners. they use the bad job market as an excuse to take advantage of employees
For those who haven't been able to source the op-amp, I found this place:
Invalid Link Removed
(no affiliation)
Just ordered some from there myself. Will report if there's any problems.
Invalid Link Removed
(no affiliation)
Just ordered some from there myself. Will report if there's any problems.
Since we've been carried this far, I was wondering if some of you more electronic savvy folks might also help in sourcing out the various parts for the pre-amp. I have gotten a bit more of an electronics education researching this stuff. I studied electronics MANY years ago but,for example, only now figured out (or at least became aware of) the alpha-numeric coding for capacitor & resistor values.
But, I haven't gotten too far as I am not sure about the preferable types (codes), voltage ratings, physical size, etc. as to be compatible with the PCB. .
Parts, as I figure (excluding pots);
1- IC Op-Amp LM4250 I saw UF's source, I found Invalid Link Removed at Digikey, I think it's the right one
Capacitors-
I'm assuming that the capacitors on Bajaman's schematic that are black/white are the electrolytic, not sure about polarity (or if there is polarity).
3- 1uF radial electrolytic capacitors
2- 10uF radial electrolytic capacitors
1- 120pF capacitor type? tantalum?
1- 500pF capacitor "
1-1.8nF capacitor "
1- 47nF (.047uF) capacitor "
Resistors 1/4W? metal?
1- 10K
1- 100K
1- 220K
1- 1.5M
2- 2.2M
I think this is a complete list, any help/corrections would be greatly appreciated!
But, I haven't gotten too far as I am not sure about the preferable types (codes), voltage ratings, physical size, etc. as to be compatible with the PCB. .
Parts, as I figure (excluding pots);
1- IC Op-Amp LM4250 I saw UF's source, I found Invalid Link Removed at Digikey, I think it's the right one
Capacitors-
I'm assuming that the capacitors on Bajaman's schematic that are black/white are the electrolytic, not sure about polarity (or if there is polarity).
3- 1uF radial electrolytic capacitors
2- 10uF radial electrolytic capacitors
1- 120pF capacitor type? tantalum?
1- 500pF capacitor "
1-1.8nF capacitor "
1- 47nF (.047uF) capacitor "
Resistors 1/4W? metal?
1- 10K
1- 100K
1- 220K
1- 1.5M
2- 2.2M
I think this is a complete list, any help/corrections would be greatly appreciated!
Yes, that'll do.
These are polarised. Bajaman's board layout has the "+" terminal marked (but you might need to zoom in a bit). If you want to spend a tiny bit more, consider using tantalum beads here for a slightly more compact build.
The last one is 47nF (0.047uF), not 47p. Just in case...
You can sub 470pF for the 500pF without problems if that's easier for you to find.
I used whatever was lying around in my parts box here. Film or good ceramics would be fine.
1/4W metal film will be ideal.
Pots, wire, 0.8mm drill bit. Maybe IC socket, but not necessary. Consider getting a spare one of everything, it won't add much to the cost (relative to shipping) and will save headaches just in case.
Been busy:
(photo exposure gear, no in-progress photos here because it's a darkroom op)
In the etchant.
Almost done.
24 boards ready for cutting.
Unfortunately, cutting will have happen later. Another employment-related issue has cropped up and is going to need dealing with. Will keep pushing this forward whenever I get a chance.
Have a good Sat night all!
(photo exposure gear, no in-progress photos here because it's a darkroom op)
In the etchant.
Almost done.
24 boards ready for cutting.
Unfortunately, cutting will have happen later. Another employment-related issue has cropped up and is going to need dealing with. Will keep pushing this forward whenever I get a chance.
Have a good Sat night all!
I'm no expert but my preference is I tried to stay away from any ceramic components. everything is metal film. for the 120pf and 500pf I bought mica caps. I also bought a gold plated IC socket so that I can pop in other opamps and see what they sound like. all the components are pretty cheap, even the pots
Update: got the boards cut. Just need the edges cleaning up and checking over.
My highly advanced fibreglass sheet cutting equipment.
Boards.
My highly advanced fibreglass sheet cutting equipment.
Boards.
Just mailed out the boards - expect a present from the mailman sometime soonish.
In hindsight, I'm not super-happy with the quality of the results here. They should work but aren't as clean as I'd like. Homebrew photo-etch boards are fine for one-off prototypes but QC is too difficult when making multiples.
If there's demand for more boards please let me know and I'll look at having them made by a real PCB house. I'm guessing that we'd need to order 20 or so to make the numbers work.
In hindsight, I'm not super-happy with the quality of the results here. They should work but aren't as clean as I'd like. Homebrew photo-etch boards are fine for one-off prototypes but QC is too difficult when making multiples.
If there's demand for more boards please let me know and I'll look at having them made by a real PCB house. I'm guessing that we'd need to order 20 or so to make the numbers work.
A lot of op-amps will want more current on pin 3 than the 2M2 resistors will provide. If you're wanting to experiment you might want to think about using 220k instead. Current consumption will go up but you'll be able to drive a wider range of chips.
thanks for the tip. so would stepping the voltage to 18 volts help when using other opamps while using the 2.2M resistor?
My guess would be no - that's only a 2x increase and you're looking for 10x to 100x. But that's just a guess. Won't hurt to try it.
(NB, check the opamp voltage rating first, of course!)
(NB, check the opamp voltage rating first, of course!)
so is running the LM4250 on 9 volts with the 220K resistor safe? the specs sheet claims the LM4250 can tolerate up to 18 volts. I'd rather solder a resistor only once instead swapping them
