SOLSTICE: Even easier PT2399 reverb!

Started by merlinb, May 04, 2012, 04:39:15 PM

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mremic01

Well, I've actually got two Solstice PCBs that I built side by side. One is part of a multifx unit and I have FSa and FSc jumpered, with the input true bypassed. The other one is in its own enclosure and the LED works, but there's no reverb. I just put the Jfet tester together from the Fetzer Valve page, and I'm getting readings from .8 to 1.5 for various J201s. Is that supposed to be a negative value? My meter is reading positive with the leads set up as per the schematic.
Nyt brenhin gwir, gwr y mae reit idaw dywedut 'y brenhin wyf i'.

psychedelicfish

VGSoff means the gate to source voltage where the device will be "off" if you go more negative, or "on" if you go more positive (in the case of JFETs). In the Fetzer Valve tester, you're measuring the source to ground voltage when the device is sitting on it's turn off voltage. So yes, your positive voltages are normal, and your JFETs are fine.

Check and double check your wiring around the JFET. The black strip on the diode should be pointing towards the 1M resistor and 10n capacitor. Make sure you have a 1M resistor in there. If the diode is right, try lowering the value of the resistor. I'm working on something on the breadboard ATM, and it uses JFET switching similar to this, but I'm using 10k rather than 1M, and everything works perfectly.
If at first you don't succeed... use bigger transistors!

Jdansti

Make sure you have +5v on pin 1 of the PT2399.
  • SUPPORTER
R.G. Keene: EXPECT there to be errors, and defeat them...

thomasha

Hi, I tried this build and it worked!

And I made my own layout in a different kind of way. I want to box it in a 1590a so I needed a two side PCB, but I only had one sided boards, had to try something new for me:

https://www.dropbox.com/s/ndkj9s9hg29pcvx/SolsticeAll.pdf?dl=0

the CI's and some resistors are at the copper side,
later I post some pictures.

Thomas

thomasha

Hi,
the pictures of my build:




It's working, and soon it will be enclosed in a 1590a box =D
Cheers,
thomas

disto

This looks interesting, I have a few spare PT2399's left so I might give this a go. Does anyone have a video or sound clip? The dropbox mp3 link is dead now.

Congratulations on the 1590a pcb Thomas, looks neat. Have you tried double sided board?

thomasha

Hi,
it's a single sided board, I just made a layout where I solder some components on the copper side to save some space.
A double sided would be much better I guess, but this was my first experiment.

Thomas

sanjay dubey

hello to all, Firstly thank you Merlin for posting such a nice build and everybody else for posting their experiences that they gained along their travels. This is my second pedal around PT2399(first was a cave dweller delay).  I have rectified the fsc-fsb labelling error from my build after reading about it in the earlier discussions(I felt that the 9 volt battery was getting hot but didn't had the courage to discourse from the documentation ;D). My issue is that I am getting no reverb! clean sound on both the states of spdt I used. any suggestion? uploading photographs soon after registering on photobucket :P thank you

thomasha

I had the same problem, and one pt was getting hot...
it happened sometimes when I connected the power jack. It was probably the latchup problem.

Check if the pt's are hot, if there is no effect at all it's probably the first one.
When I have the latchup problem i just unplug the 9v wait until the capacitors discharge and connect it again. It worked for me.

I really don't know what is the latchup problem with the pt2399, but it's pretty common with the little angel circuit too, but for a different reason.

Check the voltages at your pt2399, and signal paths.



merlinb

#69
Quote from: disto on January 16, 2015, 07:39:16 PM
This looks interesting, I have a few spare PT2399's left so I might give this a go. Does anyone have a video or sound clip? The dropbox mp3 link is dead now.
I recommend the Equinox II rather than the Solstice:
http://valvewizard.co.uk/equinox.html

QuoteI had the same problem, and one pt was getting hot...
it happened sometimes when I connected the power jack. It was probably the latchup problem.
Check if the pt's are hot, if there is no effect at all it's probably the first one.
When I have the latchup problem i just unplug the 9v wait until the capacitors discharge and connect it again. It worked for me.
Make sure pins 3 and 4 of the PT2399s are BOTH grounded. This was missing from my original Solstice circuit and does cause some PT2399 samples to latch up.

sanjay dubey

Quote from: thomasha on January 31, 2015, 08:25:58 PM
I had the same problem, and one pt was getting hot...
it happened sometimes when I connected the power jack. It was probably the latchup problem.

Check if the pt's are hot, if there is no effect at all it's probably the first one.
When I have the latchup problem i just unplug the 9v wait until the capacitors discharge and connect it again. It worked for me.

I really don't know what is the latchup problem with the pt2399, but it's pretty common with the little angel circuit too, but for a different reason.

Check the voltages at your pt2399, and signal paths.

going to short the 3 and 4 pin that may be the culprit..



sanjay dubey

going to short the 3 and 4 pin that may be the culprit.
in the mean time here is the Solstice :)... still needs some tweaking...
(http://i1117.photobucket.com/albums/k598/sanjaydubey/Image1392_zpssj46bx5c.jpg)