Do you mean? Не укључујте струју.
Dang it, I sure hope I'm not getting the Monty Python translation:
Желео бих да ти мазим дно.
But seriously ZM, forget the surface mount, work on making the device "cool looking" in a Soviet Heavy Duty look. I mean, you got the Zen Amount knobs, the Fugly switch and the Origin selector down pat... i mean, you're halfway out there with truly ZM weirdness... Never mind the back panel! ;-D
How about just go all out and do it in cyrillic with a Soviet Nuklear Nomenklature Cachet? Design a 20 lb ( 9.6 Kg ) box that would make us proud -and FedEx rich.
Make a DIY product that actually looks better than a D'Agostino with his over the top jewelry stuff... Make it, interesting looking. OK, MORE interesting looking. Something that looks like it survived the KGB.
The Chernobyl Audio Collection, by ZM, realized by Gianluca. Something that is between what we have in a metrology lab and what would have been in the control room of a large Soviet nuke plant... Oh, no LEDs... heck, no... real 2 watts red lamps on the front panel.
Something that looks like you gotta drink half a bottle of vodka to figure out how it works!
Černobilska audio kolekcija for us Westerners.
You claim you live behind the Iron Curtain... OK then... PROVE IT. 😀 😀
Audio. Don't change it. It's really there. You've achieved it. Take a rest.
Dang it, I sure hope I'm not getting the Monty Python translation:
Желео бих да ти мазим дно.
But seriously ZM, forget the surface mount, work on making the device "cool looking" in a Soviet Heavy Duty look. I mean, you got the Zen Amount knobs, the Fugly switch and the Origin selector down pat... i mean, you're halfway out there with truly ZM weirdness... Never mind the back panel! ;-D
How about just go all out and do it in cyrillic with a Soviet Nuklear Nomenklature Cachet? Design a 20 lb ( 9.6 Kg ) box that would make us proud -and FedEx rich.
Make a DIY product that actually looks better than a D'Agostino with his over the top jewelry stuff... Make it, interesting looking. OK, MORE interesting looking. Something that looks like it survived the KGB.
The Chernobyl Audio Collection, by ZM, realized by Gianluca. Something that is between what we have in a metrology lab and what would have been in the control room of a large Soviet nuke plant... Oh, no LEDs... heck, no... real 2 watts red lamps on the front panel.
Something that looks like you gotta drink half a bottle of vodka to figure out how it works!
Černobilska audio kolekcija for us Westerners.
You claim you live behind the Iron Curtain... OK then... PROVE IT. 😀 😀
Audio. Don't change it. It's really there. You've achieved it. Take a rest.
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When Papa started PL, on his property at FH, he first made Engine Room - his own CNC milling facility
Now, ZM preparing own (small, 500mm*500mm) CNC gadget, mainly to keep everything I can in house, minimizing outsourcing work already shown as cunning
When I'm done with that, besides doing all front plate/back plate work by my self, I'll start working on supermegagigaultra iteration of Iron Pumpkin in 3 boxes (PSU and Logic and TFT in one, then separate everything audio/channels), which will allow inclusion of all possible gimmicks - stand by, remote amp triggering, buffered aux outputs ( also for Rec)
and then it'll cost 10K$, "right at your door"
- no function titles at all, it'll just add to mythology; to use my preamp, one needs brain engaging
I've finished the Iron Pre boards, made the cabinet and wired the AC side of things while I wait for a fuse drawer for the IEC (didn't come with one). Input/output wiring and testing soon. I've included a photo of progress so far. My question is do you see anything at this stage that looks wrong, questionable or just bad practice. I continuity checked the AC side; everything appears to be connected to everything. On the terminal block I get beeps between the positive and neutral (red and black) but not the ground. Is that because the transformers are in the circuit? Trying to minimize future smoke!
I'm having a strange problem getting my Iron Pre SE build finished.
The voltages and DC null adjustments all went fine. Then I closed the jumpers and gave it a try.
There was something very wrong with the volume control. It was kind of causing the music to "pan" from right to left, or maybe controlling one side while the other was unaffected, so I shut it down. It seems I hooked up the pot backwards so I switched the cw and ccw connections. With that done, one channel is working correctly, but the other channel has no sound unless the volume pot is turned to maximum.
I disconnected the volume pot and it seems to be measuring normal by itself (both sections). But when I hook it up to the circuit, I get wierd measurements.
If I measure across CCWR and WIPR I see a range from 0R and the bottom of the pot and 10k at the top.
However, If I measure resistance between CCWL and WIPL, I get a range from 0 to 330R max.
To confirm, I disconnected the circuit from that section of the pot and it reads from 0R to 10K like the other channel.
Of course I gave the board a look-over for solder bridges or a stray wire clipping shorting something out... nothing so far.
Any help appreciated,
The voltages and DC null adjustments all went fine. Then I closed the jumpers and gave it a try.
There was something very wrong with the volume control. It was kind of causing the music to "pan" from right to left, or maybe controlling one side while the other was unaffected, so I shut it down. It seems I hooked up the pot backwards so I switched the cw and ccw connections. With that done, one channel is working correctly, but the other channel has no sound unless the volume pot is turned to maximum.
I disconnected the volume pot and it seems to be measuring normal by itself (both sections). But when I hook it up to the circuit, I get wierd measurements.
If I measure across CCWR and WIPR I see a range from 0R and the bottom of the pot and 10k at the top.
However, If I measure resistance between CCWL and WIPL, I get a range from 0 to 330R max.
To confirm, I disconnected the circuit from that section of the pot and it reads from 0R to 10K like the other channel.
Of course I gave the board a look-over for solder bridges or a stray wire clipping shorting something out... nothing so far.
Any help appreciated,
I would disconnect the terminal block from the inlet to just make sure that filtered inlet isn't causing the beeps. I think there may be some part of the filter that may cause a beep but I may be wrong. What color is L and what color is N coming out of the IEC inlet?
if beep with powerswitch on and no beep with powerswitch off, then good
just take proper ohmic measurement - if showing few dozen of Ohms, that's OK, Donuts primaries
if close to 0 Ohms, something is fishy
arrange some plastic cover for live connection block, too close to fingers when you need to operate trimpots
re-check resistors on buffer input
Thanks. I’m getting 41 ohms across the red and black primaries on both sides. So all is good then? Makes no difference whether power switch is on or off.
that seems good
clarify
then you didn't do something properly
do not energize anything before you repair a mistake; powerswitch must do its function - keeping circuit closed or open
@getgoin try these for terminal connections
https://www.mouser.com/ProductDetail/TE-Connectivity/1-1776302-2?qs=ZD3%2BwFPSULxv7vsa5Q0gOA==
I also add terminals on the secondaries so you can test what your transformers are putting out. I once wired a transformer incorrectly and that saved me from blowing everything up because I ignored the first warning of a blown fuse.
https://www.mouser.com/ProductDetail/TE-Connectivity/1-1776302-2?qs=ZD3%2BwFPSULxv7vsa5Q0gOA==
I also add terminals on the secondaries so you can test what your transformers are putting out. I once wired a transformer incorrectly and that saved me from blowing everything up because I ignored the first warning of a blown fuse.
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OK. Power switch IS turning ac to terminal block on and off. ( I have not plugged it in). When I said earlier that it didn't make a difference, I meant that regardless of the position of the on/off switch there is 41 ohms across red/black primaries. The power switch is functioning as expected: cuts power to terminal block/transformers. By "both sides" I mean I have two transformers and I get 41 ohms between the red/black primaries of each transformer. Is this now sounding OK? I made a shield for the terminal block also. In my wiring red wires from the IEC are line voltage, black is neutral.
Hooked the Iron Pre up to dim bulb tester. Everything fine. set v- and v+ to 15.0 volts. easy. Working on the following step: (I have V4 pcbs):
I can adjust P6 to get .014 volts at R37 on both boards. adjusting P4 at R34 is getting whacko results: about -14.0 volts. I'm measuring between R34 and ground. Where are the test points mentioned? Ideas? My DMM autoranges. I can't manually set it to millivolts. Ideas?
That's why... It says measure "across" R34 and R37. 🙂 Probe on each side of the resistor.
Square pads right next to those resistors.
Edited to add for clarity - So, one measurement across R37 (which seems to have gone well). Then once more across R34 (not R34 to GND).
Unfortunately, I wasn't measuring across R37 when I got the good measurement.
Here's what I get when I measure ACROSS R34 andR37:
Right PCB Left PCB
R34 .004 volts .000 volts
R37 .000 volts .000 volts
R34 .009 volts .009 volts (measured at test points above R40) If these are the actual test points shouldn't the values be the same as measured across the resistors?
R37 .009 volts .009 volts (measured at test points near R39)
When I adjust P4 and P6 the voltages don't change. I turned P4 and P6 a lot. There was no mechanical resistance to the turns but the voltage wasn't changing either so I stopped.
Here's what I get when I measure ACROSS R34 andR37:
Right PCB Left PCB
R34 .004 volts .000 volts
R37 .000 volts .000 volts
R34 .009 volts .009 volts (measured at test points above R40) If these are the actual test points shouldn't the values be the same as measured across the resistors?
R37 .009 volts .009 volts (measured at test points near R39)
When I adjust P4 and P6 the voltages don't change. I turned P4 and P6 a lot. There was no mechanical resistance to the turns but the voltage wasn't changing either so I stopped.
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everything needed for setting is already written on schematic
red probe on one test point, black probe on second test point
test points are practically one on each end of 1R resistor
voltage sag across 1R resistor is actually showing current through same, effectively through buffer itself
R39 for positive phase buffer (fiddle with P4)
R40 for negative phase buffer (fiddle with P6)
when that done, set buffer output DC offset to zero - red probe at appropriate jumper pin (marked "1" on pcb), black probe to GND (any convenient place on pcb)
P3 for positive side DC Offset
P5 for negative side DC Offset
edit - enclosed parts placement pic; Iq setting points marked with red; DC Offset points marked with green
red probe on one test point, black probe on second test point
test points are practically one on each end of 1R resistor
voltage sag across 1R resistor is actually showing current through same, effectively through buffer itself
R39 for positive phase buffer (fiddle with P4)
R40 for negative phase buffer (fiddle with P6)
when that done, set buffer output DC offset to zero - red probe at appropriate jumper pin (marked "1" on pcb), black probe to GND (any convenient place on pcb)
P3 for positive side DC Offset
P5 for negative side DC Offset
edit - enclosed parts placement pic; Iq setting points marked with red; DC Offset points marked with green
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