Have a look at mine in post #395 above!
Have to say I'm very happy with mine. I've had a few heart attacks along the way. One was I had remounted the boards in the box and when I reassembled, I had a terrible buzz in one channel. Couldn't see anything wrong. Eventually in preparation for resoldering stuff on the board, I used some compressed air to blow off the board - my eye caught something fly, plugged back in the board, and it worked great! Must have been a bit of swarf or something from the case!!!!
Also, I had a slight channel imbalance, and sometimes the centre image would wander a bit from side to side. Only when I was working at the above did I see that somehow I had put in a op134 one side and a op27 the other. Put in the second op27 and now everything is AOK. Must be my eyesight starting to go cos the writing is impossible to read on the opamp!
Now I have to make the boxes look a bit sexy - I got some name plates engraved today, need to machine some wood for some nice side cheeks for the cases.
Good luck - oh and on the caps, I did have to bend the leads on the caps to offset them from one another a bit to make them all fit.
Fran
Have to say I'm very happy with mine. I've had a few heart attacks along the way. One was I had remounted the boards in the box and when I reassembled, I had a terrible buzz in one channel. Couldn't see anything wrong. Eventually in preparation for resoldering stuff on the board, I used some compressed air to blow off the board - my eye caught something fly, plugged back in the board, and it worked great! Must have been a bit of swarf or something from the case!!!!
Also, I had a slight channel imbalance, and sometimes the centre image would wander a bit from side to side. Only when I was working at the above did I see that somehow I had put in a op134 one side and a op27 the other. Put in the second op27 and now everything is AOK. Must be my eyesight starting to go cos the writing is impossible to read on the opamp!
Now I have to make the boxes look a bit sexy - I got some name plates engraved today, need to machine some wood for some nice side cheeks for the cases.
Good luck - oh and on the caps, I did have to bend the leads on the caps to offset them from one another a bit to make them all fit.
Fran
Yes, they come in all shapes and sizes ... please be a little more specific about which value/brand you bought for which part of the circuit.
The latest VSPS board is a little tight around the Vregs, I admit, but the recommended values of standard electrolytic filter caps should fit without difficulty: C4,C5 330-480uF C6,C7 100-220uF C8,C9 10-100uF
/R
I don't want this to sound rude or sarcastic, but I need a little bit bigger picture than that... It didn't look like those were fully populated the first time I saw them...
My caps are WAY bigger than that....
from Mouser Electronics, Inc
-----------------------------------------------------------------
ORDERED STOCK NUMBER SHIPPED PRICE EXTENDED
-----------------------------------------------------------------
10 291-47K-RC 10 0.070 0.70
R1
Xicon 1/4W 5% Carbon
10 291-220-RC 10 0.070 0.70
R2
Xicon 1/4W 5% Carbon
10 291-680-RC 10 0.070 0.70
R3
Xicon 1/4W 5% Carbon
10 291-33K-RC 10 0.070 0.70
R4
Xicon 1/4W 5% Carbon
10 291-220K-RC 10 0.070 0.70
R5
Xicon 1/4W 5% Carbon
10 291-47-RC 10 0.070 0.70
R6
Xicon 1/4W 5% Carbon
10 871-B81123C1332M 10 0.440 4.40
C1
EPCOS Polypropylene
10 871-B81123C1103M 10 0.820 8.20
C2
EPCOS Polypropylene
6 594-BFC236825475 6 2.490 14.94
C3
Vishay/BC Components
6 863-NE5532NG 6 1.050 6.30
U1
ON Semiconductor Amp
My caps are WAY bigger than that....
from Mouser Electronics, Inc
-----------------------------------------------------------------
ORDERED STOCK NUMBER SHIPPED PRICE EXTENDED
-----------------------------------------------------------------
10 291-47K-RC 10 0.070 0.70
R1
Xicon 1/4W 5% Carbon
10 291-220-RC 10 0.070 0.70
R2
Xicon 1/4W 5% Carbon
10 291-680-RC 10 0.070 0.70
R3
Xicon 1/4W 5% Carbon
10 291-33K-RC 10 0.070 0.70
R4
Xicon 1/4W 5% Carbon
10 291-220K-RC 10 0.070 0.70
R5
Xicon 1/4W 5% Carbon
10 291-47-RC 10 0.070 0.70
R6
Xicon 1/4W 5% Carbon
10 871-B81123C1332M 10 0.440 4.40
C1
EPCOS Polypropylene
10 871-B81123C1103M 10 0.820 8.20
C2
EPCOS Polypropylene
6 594-BFC236825475 6 2.490 14.94
C3
Vishay/BC Components
6 863-NE5532NG 6 1.050 6.30
U1
ON Semiconductor Amp
Those ARE big! 😱
Voltage rating affects size. 250V caps are much bigger than 50V or even 100V types. Obviously for the VSPS you dont need 250V, though lower ratings are not always available. I notice Mouser doesn't appear to offer anything smaller in polypro.
Voltage rating affects size. 250V caps are much bigger than 50V or even 100V types. Obviously for the VSPS you dont need 250V, though lower ratings are not always available. I notice Mouser doesn't appear to offer anything smaller in polypro.
"I notice Mouser doesn't appear to offer anything smaller in polypro."
Exactly.. Digi-Key didn't either.
Any idea's?
Thank you again for the help and support. It is appreciated and has NOT gone unnoticed. 🙂
Wait!... Edit to add....
Finally I can say I have a big something!
🙄
Exactly.. Digi-Key didn't either.
Any idea's?
Thank you again for the help and support. It is appreciated and has NOT gone unnoticed. 🙂
Wait!... Edit to add....
Finally I can say I have a big something!
🙄
Mouser actually does have Wima MKP2 in stock for both values in 100V rating
MKP2-3300/100/5
MKP2-.01/100/5
for about 50c each...
I'm not sure why they didn't come up when I first searched. You can use the ones you have by if you mount them externally to the board (glue them to the case nearby and solder an extension lead) but I can understand if aesthetically you might decide to reorder.
You can also consider mica and polycarbonate types. Mouser sells the mica (CD30FD103JO3,CD19FD332FO3), but polycarb only in 0.1uF not 3.3n.
-R
MKP2-3300/100/5
MKP2-.01/100/5
for about 50c each...
I'm not sure why they didn't come up when I first searched. You can use the ones you have by if you mount them externally to the board (glue them to the case nearby and solder an extension lead) but I can understand if aesthetically you might decide to reorder.
You can also consider mica and polycarbonate types. Mouser sells the mica (CD30FD103JO3,CD19FD332FO3), but polycarb only in 0.1uF not 3.3n.
-R
Is there another place that has "the right" parts that I can order ones and twos (not minimum 50K pieces) from?
The minimum order on the Wima caps at Mouser is 1, hard to imagine anything more generous to the hobbyist than that. Digikey usually allows single unit orders too. Of course theres a surchage if the total order is less than a certain amount.
www.partsconnexion.com has mica caps and such in single unit quantities and no minimum order. And, according to the email I got this morning, they are having a 15% discount on everything sale right now. Again.
/R
www.partsconnexion.com has mica caps and such in single unit quantities and no minimum order. And, according to the email I got this morning, they are having a 15% discount on everything sale right now. Again.
/R
Will the 100v Wima's fit?
And a sale would be a good excuse to buy a bunch of unneeded stuff from P con. 😀
And a sale would be a good excuse to buy a bunch of unneeded stuff from P con. 😀
I bought all mine from:
www.radionics.ie
I don't know what the story would be with shipping overseas, but the stuff is basically RS.
Bag of 10 x 100uF 35V capacitors, elna cerafine are I think about €6 or so (per pack). 5 of the 470uF ones were a bit dearer at €14.
On the picture, there is a limit here on the forum as to the size of pic you can post, limitied to something like 1000 by 1000 pixels I think. If you want bigger pics, or a copy of the part numbers I used, just post back here.
Fran
www.radionics.ie
I don't know what the story would be with shipping overseas, but the stuff is basically RS.
Bag of 10 x 100uF 35V capacitors, elna cerafine are I think about €6 or so (per pack). 5 of the 470uF ones were a bit dearer at €14.
On the picture, there is a limit here on the forum as to the size of pic you can post, limitied to something like 1000 by 1000 pixels I think. If you want bigger pics, or a copy of the part numbers I used, just post back here.
Fran
I just finished a VSPS! I designed my own PCB to suit the parts I had on hand. I'll use it with my Kookaburra. First listen was excellent, good sound, no hum or buzz at all. I'm very happy with it 😉
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
I tried the 637bp on the phonoclone with poor result.
It's oscillating badly, I tried some decoupling without any result.
Any idea how to stabilize it in this application ?
It's oscillating badly, I tried some decoupling without any result.
Any idea how to stabilize it in this application ?
franksmith said:
No idea but mine works fine. Where your decoupling caps far away from the opamps?
No, they where pretty close.
I raised the gain of the first stage up to 50 to stabilize it without result.
I raised the gain of the first stage up to 50 to stabilize it without result.
You can't compare the VSPS and the Phonoclone here. Especially the first stage of the phonoclone, which is inverting and probably most importantly doesn't have any capacitor on the feedback to limit the gain at high frequencies like the VSPS does.
The VSPS and the second stage of the phonoclone have the RIAA eq in the feedback loop, these circuits are less likely to oscillate as a result.
A small capacitor in parallel with R2 may help, adding ceramic bypass caps at the power pins of the opamp may also do the trick... "Pretty close" or just having electrolytics without additional bypassing is likely insufficient.
I'm a little surprised that increasing the gain 20dB didnt help. Without knowing which layout or PCB revision you are using, however, I cant really comment further.
/R
The VSPS and the second stage of the phonoclone have the RIAA eq in the feedback loop, these circuits are less likely to oscillate as a result.
A small capacitor in parallel with R2 may help, adding ceramic bypass caps at the power pins of the opamp may also do the trick... "Pretty close" or just having electrolytics without additional bypassing is likely insufficient.
I'm a little surprised that increasing the gain 20dB didnt help. Without knowing which layout or PCB revision you are using, however, I cant really comment further.
/R
I'm using the phonoclone be.
I have some propylene 0.1 uf pretty close from the +vs and -vs. I'm using socket so I can easily solder somes ceramics ones direct on the socket legs from the bottom.
My opa627 work very well but I only have two of them and two 637 so I would had appreciate to use the 637 🙂
I tried the 637 on the second stage (with the riaa) also with the same oscillation problem.
Sylvain
I have some propylene 0.1 uf pretty close from the +vs and -vs. I'm using socket so I can easily solder somes ceramics ones direct on the socket legs from the bottom.
My opa627 work very well but I only have two of them and two 637 so I would had appreciate to use the 637 🙂
I tried the 637 on the second stage (with the riaa) also with the same oscillation problem.
Sylvain
Ok, that helps narrow things down.
I don't know why no one has been able to get either a OP37 or OP637 working in first stage of the phonoclone. On paper it is supposed to be stable at gains above +5, and I would expect similar performance when configured inverting. In practice however, it seems to be tough.
With the BE, try ceramic 0.1 uF caps in C8B and C9B, or better yet between the opamp socket pins to the ground pad of C8B and C9B. As I suggested above, also consider putting a small capacitor in parallel with R2.�@Keep electrolytics in C8 and C9.
/R
I don't know why no one has been able to get either a OP37 or OP637 working in first stage of the phonoclone. On paper it is supposed to be stable at gains above +5, and I would expect similar performance when configured inverting. In practice however, it seems to be tough.
With the BE, try ceramic 0.1 uF caps in C8B and C9B, or better yet between the opamp socket pins to the ground pad of C8B and C9B. As I suggested above, also consider putting a small capacitor in parallel with R2.�@Keep electrolytics in C8 and C9.
/R
franksmith said:
Actually after a bit of testing OPA637 didn't work in my VSPS either. It goes fine but then every now and again it would go pop and sound terible. Like turning my TT off while connected to the VSPS would make it do this. OPA2132 is fine though. So I guess it wasn't completely stable after all.