No, the friend who gave me the oscilloscope decided to surprise me I guess, had no clue until I opened the package...
OMG...an oscilloscope too ?
Your like an engineer already !!
The red LED's on your TPR's.......are they 3mm and will 1.5v ones be OK ?
I've also found 1.8 - 2.4 volts @ 20 ma.
Which ones do I need ?
Your like an engineer already !!
The red LED's on your TPR's.......are they 3mm and will 1.5v ones be OK ?
I've also found 1.8 - 2.4 volts @ 20 ma.
Which ones do I need ?
Dac looks almost finished !!
How much to do now ?
Caps in the CD Player yet ?
Not enough time - I know this problem😱
How much to do now ?
Caps in the CD Player yet ?
Not enough time - I know this problem😱
Very generous that friend of mine...to say the least.
Engineers know how to use the oscilloscope 😉 I don't, yet.
3mm is fine, but 1,5V is not enough, the diodes act as the voltage reference(1,85+1,85+1,25=4,95Vdc) in this circuit. You could replace the two in series with a trimpot and tune voltage that way.
The ones I used(sorry for the Swedish on that site)
With these I get 4,95Vdc w/out load and 4,73Vdc w load.
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Not much left to do on the DAC, but critical part like TCXO and transformers are still to be ordered.
Haven't gotten around to put the caps in the cd-player yet.
I have so many projects to build now that it's insane.
100W/4ohm digital amp
3 tube preamps.
One remote controlled preamp w display and input selector
My B1 preamp.
My 3 cd-players
My Dac.
My tube amp I get on friday.
AND learn how to use an oscilloscope. Old but very high quality.
Got a little bit done today. Moved my workstation from the kitchen table to the delight of my better half.
Needs dusting, I know...
Needs dusting, I know...
Just finished setting the 100R trimpots I use between 2SK170 and the tube-socket.
Aimed for 40mV over a 10R resistor between a 9V battery and pin1(drain), +- 5% was ok, I got 39,8mV on both. Happy with that.
Aimed for 40mV over a 10R resistor between a 9V battery and pin1(drain), +- 5% was ok, I got 39,8mV on both. Happy with that.
This build is now about $5 short of $300...
But why complain, I've gotten so much fun DIY-stuff for free recently 🙂
But why complain, I've gotten so much fun DIY-stuff for free recently 🙂
Build is not abandoned, waiting for some parts and to afford to order other parts.
Also I've been busy with this tube amp
I found the fault, a resistor that was broken(a 51R resistor responsible for poweringen one channel of the amp). Also I'll put a second on-off switch (on B+) so that I can switch on heaters, and then 20-30sec later switch on B+.
A manual softstart of sorts.
Also I've been busy with this tube amp
I found the fault, a resistor that was broken(a 51R resistor responsible for poweringen one channel of the amp). Also I'll put a second on-off switch (on B+) so that I can switch on heaters, and then 20-30sec later switch on B+.
A manual softstart of sorts.
Done 🙂 Not pretty, but it works, I'll make it pretty later when I've tested it w tubes in place. Enough OT, sorry.
Got the PS's needed for the ECC86 output today.
24Vdc/1A and 6Vdc/1A.
24Vdc/1A and 6Vdc/1A.
An externally hosted image should be here but it was not working when we last tested it.
I've ordered a custom transformer for the DAC.
It's a toroid 60VA 230V primary.
Secondaries:
0-9Vac 1A
0-15Vac 1A
16-0-16Vac 1A
A picture of a friends transformer from the same company that's making mine.
This way I get away with using one transformer and it was actually the cheapest option.
This leaves room for a copper "wall" between transformer and DAC (and later tube output).
It's a toroid 60VA 230V primary.
Secondaries:
0-9Vac 1A
0-15Vac 1A
16-0-16Vac 1A
A picture of a friends transformer from the same company that's making mine.
This way I get away with using one transformer and it was actually the cheapest option.
This leaves room for a copper "wall" between transformer and DAC (and later tube output).
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Could someone please give me the search words for ebay or link me to a place where I can get a dip socket with the right dimensions that can be modified to be a TCXO-socket(cut to size and remove excess pins I guess). I want this in part to be able to swap/upgrade TCXO and also to change them in time as they age.
With transformer the total so far comes to $387.
Still left to buy:
TCXO( price depends on which I chose) and a top for the enclosure (15usd)
Still left to buy:
TCXO( price depends on which I chose) and a top for the enclosure (15usd)
I have 4pcs OPA604 and 2pcs NE5534.
I'm thinking of putting the entire thing together when I get the transformer and TCXO using OPA604 for I/V and Buffer/Filtering.
Listen to the dac this way for a while before putting in the ECC86 outputstage.
Will this do as a TCXO-socket? Either breaking of 4 pins or two rows and removing unused pins(this approach would make for a more stable socket).
I'm thinking of putting the entire thing together when I get the transformer and TCXO using OPA604 for I/V and Buffer/Filtering.
Listen to the dac this way for a while before putting in the ECC86 outputstage.
Will this do as a TCXO-socket? Either breaking of 4 pins or two rows and removing unused pins(this approach would make for a more stable socket).