anatech said:
Thanks, I think. It's actually quite an expanse of workspace on the odd occasion that it's clean. I think the last time that happened was the day after I built it.
Basement: not so much. In central Texas, the water table is likely to be single digits of feet from the bottom of the dining room table. Plus, it floods more in this region than anywhere else in the country. Plus, I live next door to a natural spring. And a creek runs behind my house... that turns into a torrent after heavy rains. Thank God, my house is at the top of a low rise (not a hill really); both ends of my street are in the "100 year" floodplain.
Hi Stocker,
Electronics and water. Not a good mix. It must be terribly warm in the garage some days. As a Canuck, I hide in the basement on those days. Comfort. So, consider building a concrete block house just for you and your stuff. It's secure and huricane resistant.
-Chris
I have had the same experience. Occansionally I pick out the good stuff and sweep the rest into the garbage. Survival.
Electronics and water. Not a good mix. It must be terribly warm in the garage some days. As a Canuck, I hide in the basement on those days. Comfort. So, consider building a concrete block house just for you and your stuff. It's secure and huricane resistant.
-Chris
My Electronics Workbench
Right now is mostly theoretically preparations and designs.
Have like 3-4 projects circuits going but not anything completed yet.
My workbench ...
Yes, that is what they call this Computer electronics design software:
Electronics Workbench Design Suite
So I sit with Multisim and build my amplifiers with faked transistors.
The good thing I got almost unlimited supply of MOSFETs, TO3, JFETs Low Noise small signal bipolars and Power Supplies.
At no extra cost ..... !!!
My image shows whats on my workbench today.
DC input - DC output buffer amplifier.
Actually havent added 1 single capacitor at all, yet.
May have to look at some square-waves and add some pF to reduce overshoot.
It is a no feedback simple amplifier ( no need for this at gain = 1 ) with only small signal TO-92 transistors.
I have manage to get zero offset from input to output
and using my active bias current compensation technique
the bias offset current is now down so much
it cause less than 100 nV across a 100 kohm input resistor.
As seen from my image, I right now try to fight and reduce 0.004% THD at 1 kHz
14 volt peak input ( = 10 volt RMS out ) into a load of 2 kohm.
I might publish this DC-buffer, when I feel I have gotten as close to perfection I want
and if I think there is any interest at this board for such an amplifier.
Transistors used are low noise, high gain from Toshiba:
2SA970 and 2SC2240
Regards
llineup, at his virtual workbench
Lineup Audio Lab
http://lineup.awardspace.com/
cnctooltek said:
Right now is mostly theoretically preparations and designs.
Have like 3-4 projects circuits going but not anything completed yet.
My workbench ...
Yes, that is what they call this Computer electronics design software:
Electronics Workbench Design Suite
So I sit with Multisim and build my amplifiers with faked transistors.
The good thing I got almost unlimited supply of MOSFETs, TO3, JFETs Low Noise small signal bipolars and Power Supplies.
At no extra cost ..... !!!
My image shows whats on my workbench today.
DC input - DC output buffer amplifier.
Actually havent added 1 single capacitor at all, yet.
May have to look at some square-waves and add some pF to reduce overshoot.
It is a no feedback simple amplifier ( no need for this at gain = 1 ) with only small signal TO-92 transistors.
I have manage to get zero offset from input to output
and using my active bias current compensation technique
the bias offset current is now down so much
it cause less than 100 nV across a 100 kohm input resistor.
As seen from my image, I right now try to fight and reduce 0.004% THD at 1 kHz
14 volt peak input ( = 10 volt RMS out ) into a load of 2 kohm.
I might publish this DC-buffer, when I feel I have gotten as close to perfection I want
and if I think there is any interest at this board for such an amplifier.
Transistors used are low noise, high gain from Toshiba:
2SA970 and 2SC2240
Regards
llineup, at his virtual workbench
Lineup Audio Lab
http://lineup.awardspace.com/
Attachments
anatech said:Hi lineup,
Great design. Diamond buffer?
-Chris
I must admit I had a look at Per-Anders diamond buffer before starting my circuit.
QRV-05 is the name of his design:
http://www.sjostromaudio.com/hifi_files/qrv/qrv05r0schema_p1.pdf
And he in his turn took a close look at Walt Jung's original suggestion.
Read Walt's article and have a look at his circuit here:
Realizing High Performance: Buffers (Part II)
My circuit uses same idea, but replace one half with Current sources.
Including a very small constant current source, to cancel input bias current.
So it is NOT a symmetrical circuit and this may very well make distortion products, harmonics different.
Maybe more 2nd and less 3rd ???
About my active bias compensation, which i have mentioned and recommended many times at this forum:
Lineup Article January 2006: Offset Correction using Bias Compensation
My goal with this buffer circuit:
- As the voltage supply is +-30 Volt ( and the transistors can take up to +-40 volt max )
I want to try to reach at least 16 Volt RMS output, into 1 kohm
still keeping a nice square wave at 10-20 kHz and so a low distortion.
16 Volt RMS is = 22.6 Volt peak and 22.6 mA current into 1 kohm.
I would probably have to raise voltage supply to 36 volt, from now 30.
I think LM317L / LM337L ( TO-92 100 mA version ) can put out 36 volt
and so be suitable dual regulated voltage supply.
LM317L - 3-Terminal Positive Adjustable Regulator http://www.national.com/pf/LM/LM317L.html
LM337L - 3-Terminal Negative Adjustable Regulator http://www.national.com/pf/LM/LM337L.html
Regards
lineup
Banned
Joined 2002
Banned
Joined 2002
That Darned Bench
Here are two Pics of my bench on a day.
This day working on a dual YAmPm1000 Mic Pre in 19" rack case.
I have racked up a number of Yam modules in different ways. I also have been making preamps with the Talkback and Cue module cards that sound great.
I am normally a "Tube Dude" but I have had fun with the leetle transister sisters....
Here are two Pics of my bench on a day.
This day working on a dual YAmPm1000 Mic Pre in 19" rack case.
I have racked up a number of Yam modules in different ways. I also have been making preamps with the Talkback and Cue module cards that sound great.
I am normally a "Tube Dude" but I have had fun with the leetle transister sisters....
Attachments
I have to find a pic of the whole mess with some gear on it.
I was looking late at night when I saw this thread, but a good pic of the whole Thang is buried somewhere.
Look at this link to see samples of some of my work
http://photobucket.com/albums/b121/SalesBoy/
I still have to add pics. I had a website up of rare Gitty-Amps I have restored and I will add those this year. I hate snooping through who has a decent Host service so I am being a lazy-pig about it.
Here is a pic of two mike preamps I di using these small Yam cards from TalkBack modules. My friend Ken who has been selling the PM1000 preamp modules brought some of these by. I saw the cards have to of the four-Transistor amp stages on them so I mocked up a trans in-pre stage-level-line stage-out trans preamp with one. Without the EQ and other frills in the way they really cook with the Tamura trans taking the harshness off.
The gain block is really weird. The 1st transistor doesn't seem do do anything and I was told it is a current amp. There is no signal out when working properly. The gain stage will drive down to 65 ohms at 25 P-P swing.
I wish I had kept more transistor books for good circuits. It is hard to know what is quiet.
I was thinking of making a PC board (to sell) if I could modify the circuit a Leetle and mabey-baby have a version that is fatter and not infringing on Yamaha too much. The older circuits are fatter and more tony than newer Bi-Polar supply versions.
I am posting again with a Tube amp that shows a Leetle more..
I was looking late at night when I saw this thread, but a good pic of the whole Thang is buried somewhere.
Look at this link to see samples of some of my work
http://photobucket.com/albums/b121/SalesBoy/
I still have to add pics. I had a website up of rare Gitty-Amps I have restored and I will add those this year. I hate snooping through who has a decent Host service so I am being a lazy-pig about it.
Here is a pic of two mike preamps I di using these small Yam cards from TalkBack modules. My friend Ken who has been selling the PM1000 preamp modules brought some of these by. I saw the cards have to of the four-Transistor amp stages on them so I mocked up a trans in-pre stage-level-line stage-out trans preamp with one. Without the EQ and other frills in the way they really cook with the Tamura trans taking the harshness off.
The gain block is really weird. The 1st transistor doesn't seem do do anything and I was told it is a current amp. There is no signal out when working properly. The gain stage will drive down to 65 ohms at 25 P-P swing.
I wish I had kept more transistor books for good circuits. It is hard to know what is quiet.
I was thinking of making a PC board (to sell) if I could modify the circuit a Leetle and mabey-baby have a version that is fatter and not infringing on Yamaha too much. The older circuits are fatter and more tony than newer Bi-Polar supply versions.
I am posting again with a Tube amp that shows a Leetle more..
Attachments
jleaman said:
It's actually a Team Associated RC10B2 with a Futaba radio. I don't even know if they make parts for it anymore. Haven't raced it in a while to be honest. It was a lot of fun to drive though. Electric R/C has always had more of an appeal to me. No messing with fuel and all the extra junk needed to get it started and keep it running. Plus I already had a soldering iron and stuff handy. It helped knowing the people behind the counter at the local hobby shop too. I'd like to get back into racing now that brushless motors are coming down in price.
What you don't see on my workbench is my electric helicopter. That has a brushless motor
and a busted rotor blade after my last hard landing...Attachments
Banned
Joined 2002
BWRX said:
It's actually a Team Associated RC10B2 with a Futaba radio. I don't even know if they make parts for it anymore. Haven't raced it in a while to be honest. It was a lot of fun to drive though. Electric R/C has always had more of an appeal to me. No messing with fuel and all the extra junk needed to get it started and keep it running. Plus I already had a soldering iron and stuff handy. It helped knowing the people behind the counter at the local hobby shop too. I'd like to get back into racing now that brushless motors are coming down in price.
What you don't see on my workbench is my electric helicopter. That has a brushless motor
I'm thinking about getting into small r/c helis my self. yes brushless motors are cheaper now. I had the novac system in a awd hpi car that FLEW and accelerated so fast.
I still like the power and speed of a .21 tuned really good. I had a ofna 1/8 scale buggy and a kyosho landmax with 2 speed tranny and then a hpi suprent vector. ALLL fast car's.
Got any pics of heli ?
maybe email me off line
And now back to the thread
i figured id share a funny story about my work area with you guys!
my apartment complex had some big inspections coming up, and decided everything had to be fixed. i came home and every single thing in my apartment worked perfect!!!! i mean down to the missing bake/broil selector on the oven. funny thing is they looked in my closet of doom, and must have been freaked out!
i found a handy new fire extinguisher! LOL
i guess they have never seen a member of diyaudios work space before.
my apartment complex had some big inspections coming up, and decided everything had to be fixed. i came home and every single thing in my apartment worked perfect!!!! i mean down to the missing bake/broil selector on the oven. funny thing is they looked in my closet of doom, and must have been freaked out!
i found a handy new fire extinguisher! LOL
i guess they have never seen a member of diyaudios work space before.
