Hi Pete (and Mark)
Thanks very much again!
I definitely need to develop the habit of stepping back a little when I come across an obstacle (instead of jumping on the community). It seems like Mouser is laying out some traps sometimes ...
I got trapped by those little differences.
Myleftear....As Mark encouraged you I will also...if you’re going to be building up PCBs for various projects it’s a good skill to look at the characteristics of the expired parts and do your own searches for substitution parts. It will be an extremely useful skill. I’m a neophyte builder as well and it took me the better part of a year, and a number of stereo amp fixes/upgrades/builds to get somewhat competent. My personal tip..if you’re buying boards to build things (like the soft start) always buy two so you can have a blank one as a reference to check where things go and in what direction or positioning. Sometimes the pictures of the blank boards, or ones already filled, may be different versions and may not fully represent what you have in your hand.
Best, Pete
Best, Pete
Where is the best source for Mundorf caps? Mouser, digikey and partsexpress don't seem to carry them.
Mark,
Although I found the link you provided quite convincing [emoji16], I‘d like to add that following it may not ultimately lead to the _best_ source for the aforementioned parts...
Just curious...I guess you’re looking for some other project because the SoftStart boards don’t call for those caps. The Mundorf MKPs are the lowest grade they have. The Evo or Supreme Evo are better sounding for amp/pre-amp builds but they are more expensive (and much bigger). MKPs are great for crowded build situations tho..
Yes, I was searching the various forums. The Mundorfs are for the input coupling caps on a WHAMMY I just built and I want to compare how those sound compared to Solen and Jensens I have as a few people were raving about them on the build.
This is why I love DIY and this forum: its all about learning and building components that YOU like to listen to.
This is why I love DIY and this forum: its all about learning and building components that YOU like to listen to.
Yes exactly. I've got both the Solen silver and regular audio caps, plus the Jensens and was going to give the Mundorfs a shot too while I am at it. I built a stock one which is my base line, and am building a second one to experiment with various caps and opamps now.
--Tom
A note to anyone ordering that the following part numbers are incorrect on the .pdf BOM referenced above:
1 LED1 Red 5mm Red diffused LED 78-THLR6400 2.54mm
1 LED2 Green 5mm Green diffused LED 78-THLG6405 2.54mm
should be these Mouser part numbers:
1 LED1 Red 5mm Red diffused LED 78-TLHR6400 2.54mm
1 LED2 Green 5mm Green diffused LED 78-TLHG6405 2.54mm
Also note that the Omron relays are now these two models as the ones shown in the BOM .pdf are listed as obsolete (note the voltages):
653-G5Q-14-DC12
or
653-G5LE-1-ASIDC5
Happy Trails!
Did not read the whole thread (checked V2 and V3 threads though).
At some point it was asked about the R value (before the relay is powered) according to the main voltage, around 230V in Europe, around 115V in US/Japan.
There was a formula in the V2 tread to define R: Vmain^2/current/Vsecondaries; as far as I remember.
Is the proposed softstart circuit supposed to work the same for both main voltages?
Shall R be changed according to the main (i.e. according to where the circuit is used)?
At some point it was asked about the R value (before the relay is powered) according to the main voltage, around 230V in Europe, around 115V in US/Japan.
There was a formula in the V2 tread to define R: Vmain^2/current/Vsecondaries; as far as I remember.
Is the proposed softstart circuit supposed to work the same for both main voltages?
Shall R be changed according to the main (i.e. according to where the circuit is used)?
Thats an implied “Yes” in the build guide for V2 by JojoD818.
QUOTE=r_jik45;6143332] Shall R be changed according to the main (i.e. according to where the circuit is used)?[/QUOTE]
That’s also a yes; Total parallel resistance from R15 to R18 of about 45-50 ohms for 220-240VAC while for 100-20VAC it’s 30-35 ohms.
"The recommended values are the best compromise for time delay time and initial charge w/o R15 to R18 overheating."
Cheers, Pete
"if it's better to prepare 2 versions?"
I think that’s also implied in the build guide for V2 but not explicitly stated as a "No".
Oh, they do give a range of values for R15-R18 if that's what you're looking for. For 220VAC the total parallel resistance is recommended to be 45-50 ohms (so 4x180ohm 5W resistors in parallel = 45ohms). For 110-120VAC the total parallel resistance is 30-35ohms (so 4x140ohm 5W resistors in parallel =35 ohms).. Even tho the build guide initially says 4x 150-180ohm resistors the "ideas & alternatives" section says something different. Resistance calculation for parallel resistors is 1/R(total)=1/R1+1/R2+1/R3+1/R4.
For C9 just use 0.68uF (for 110-120VAC) or 0.33uF (for 220VAC). That gives about the longest delay for each voltage.
Is that what you were seeking?
For C9 just use 0.68uF (for 110-120VAC) or 0.33uF (for 220VAC). That gives about the longest delay for each voltage.
Is that what you were seeking?
Hi again Pete,
Was refering to the schematics from the store (https://cdn.shopify.com/s/files/1/1006/5046/files/SSSchematic.jpg). Not the same references but likely what I was looking for. The capacitor you are speaking about is likely the 'Radial Polypropolene Snubber' one.
Already ordered a set of resistors for 40 ohms and a capacitor of 330nF for 220-240VAC. Will check the other values for a 110-120VAC version.
Thanks again for the detailed reply.
Was refering to the schematics from the store (https://cdn.shopify.com/s/files/1/1006/5046/files/SSSchematic.jpg). Not the same references but likely what I was looking for. The capacitor you are speaking about is likely the 'Radial Polypropolene Snubber' one.
Already ordered a set of resistors for 40 ohms and a capacitor of 330nF for 220-240VAC. Will check the other values for a 110-120VAC version.
Thanks again for the detailed reply.