Hi,
I assume breadboarding an amp means building it in a temporary fashion, i.e. not fastening all the components down and not soldering everything. Questions:
* Do you use alligator clip leads for all connections? I guess it would be a god idea to buy a large pack of these. Are there any requirements for minimum wire gauge or anything else?
* I could lay out transformers, resistors and caps on a table or a piece of wood or cardboard. What do you do for tubes and their sockets? Do you leave them standing upright, resting on the socket solder tabs? Do you lay them down on the side? (That seems like a bad idea, to have the tube envelope touching something)
* Anythin else I should know and/or be careful of?
One more question that's kinda related - how should I test noise levels when picking transformer positions and orientation? Let's say I'm trying to check the effect of the power transformer on the output transformer. Obviously, I need to supply AC mains to the power transformer. Do I put a load on the secondary, or leave it unloaded (making sure the wires aren't shorting)? Does it make a difference? Also, what do I do to the output transformer? I have a scope, so the probes go at the two output (secondary) taps, I guess. Does the secondary need something like an 8 ohm load resistor? How about the primary - do I leave that open?
Thanks in advance.
Saurav
I assume breadboarding an amp means building it in a temporary fashion, i.e. not fastening all the components down and not soldering everything. Questions:
* Do you use alligator clip leads for all connections? I guess it would be a god idea to buy a large pack of these. Are there any requirements for minimum wire gauge or anything else?
* I could lay out transformers, resistors and caps on a table or a piece of wood or cardboard. What do you do for tubes and their sockets? Do you leave them standing upright, resting on the socket solder tabs? Do you lay them down on the side? (That seems like a bad idea, to have the tube envelope touching something)
* Anythin else I should know and/or be careful of?
One more question that's kinda related - how should I test noise levels when picking transformer positions and orientation? Let's say I'm trying to check the effect of the power transformer on the output transformer. Obviously, I need to supply AC mains to the power transformer. Do I put a load on the secondary, or leave it unloaded (making sure the wires aren't shorting)? Does it make a difference? Also, what do I do to the output transformer? I have a scope, so the probes go at the two output (secondary) taps, I guess. Does the secondary need something like an 8 ohm load resistor? How about the primary - do I leave that open?
Thanks in advance.
Saurav
OK, this is helping... somewhat 🙂 I see a combination of hookup wire and clip leads. I also see that having a large workspace helps, but that's obvious. From the pictures, I can't see how the tubes are set up too well. Are the sockets just sitting on the boards?
Need some help here!
Please don't look at my "breadboard"--very bad and very dangerous!
Others in this forum will post some better pics of decent breadboards--I liked John's though with all those layers of wires!!
What an animal!
Joel,
That really hurts!
Rick
Please don't look at my "breadboard"--very bad and very dangerous!
Others in this forum will post some better pics of decent breadboards--I liked John's though with all those layers of wires!!
What an animal!
Joel,
That really hurts!
Rick
Breadboards
They do not have to be so rough.
Here is a shot of John Sheerwood's set up.
Lets him make changes and presentable too. The tubing comes apart easily.
A look from the bottom
There are a few more pictures at his site. Nice for something that is close but you may want to change and are not ready to commit to a chassis yet.
Cheers
Craig Ryder
They do not have to be so rough.
Here is a shot of John Sheerwood's set up.
Lets him make changes and presentable too. The tubing comes apart easily.
An externally hosted image should be here but it was not working when we last tested it.
A look from the bottom
An externally hosted image should be here but it was not working when we last tested it.
There are a few more pictures at his site. Nice for something that is close but you may want to change and are not ready to commit to a chassis yet.
Cheers
Craig Ryder
Re: Breadboards
Love the framework, or is it the heater wiring? I'm not sure I would call it a breadboard, though. The awfulness of lash-ups seems to be in direct proportion to the fastidiousness of final construction...
So, to answer the original question, "Carefully." Lash-ups are where smoke is almost expected, so they are made (thrown together) in a way so that flames from one component don't damage another. Lots of space between components.
Ryder said:
Love the framework, or is it the heater wiring? I'm not sure I would call it a breadboard, though. The awfulness of lash-ups seems to be in direct proportion to the fastidiousness of final construction...
So, to answer the original question, "Carefully." Lash-ups are where smoke is almost expected, so they are made (thrown together) in a way so that flames from one component don't damage another. Lots of space between components.
Saurav,
No pix of my monstrosities unfortunately, but breadboarding involves, lots of space on a big plank of wood and clipleads and/or tack soldered wires. The rest is really up to you. My entire coffee table in the living room is my 813PP amp at the moment, with all the power transformers sitting on another plank on the floor behind it (no kids, smart dog), wires running all over the place as I've tried different configurations. As I was building it, I was already beginning to think how it would all go together in the end, and tried to keep it a bit similar, with it being like the amps Ryder linked, but two levels of PSU, enclosed.
The main differeece with mine is my tube sockets are on 2x2 or 3x3 pieces fo MDF, stood above the board by 1.25" nylon standoffs. That way I can easily solder to the pins directly or screw a tagstrip to the board and join a lot of wires and move the socket positions around easily. This helps and is worth the effort if you build a lot of amps.
The other method, and one I used when I 'cloned ' a classic design is to draw the dimension of the final chassis on the breadboard, and carefully test layout all the parts (pencil and paper helps too) to see how it all fitted together. I didn't like the look of the original, and the spare powertrans I was using was a LOT larger, so I didn't just copy the factory plan. Clipleaded it together, fired it up, adjusted tx positions slightly to limit tube heat and hum. Then once the final top plate was drilled,it took a couple of hours to finish.
No pix of my monstrosities unfortunately, but breadboarding involves, lots of space on a big plank of wood and clipleads and/or tack soldered wires. The rest is really up to you. My entire coffee table in the living room is my 813PP amp at the moment, with all the power transformers sitting on another plank on the floor behind it (no kids, smart dog), wires running all over the place as I've tried different configurations. As I was building it, I was already beginning to think how it would all go together in the end, and tried to keep it a bit similar, with it being like the amps Ryder linked, but two levels of PSU, enclosed.
The main differeece with mine is my tube sockets are on 2x2 or 3x3 pieces fo MDF, stood above the board by 1.25" nylon standoffs. That way I can easily solder to the pins directly or screw a tagstrip to the board and join a lot of wires and move the socket positions around easily. This helps and is worth the effort if you build a lot of amps.
The other method, and one I used when I 'cloned ' a classic design is to draw the dimension of the final chassis on the breadboard, and carefully test layout all the parts (pencil and paper helps too) to see how it all fitted together. I didn't like the look of the original, and the spare powertrans I was using was a LOT larger, so I didn't just copy the factory plan. Clipleaded it together, fired it up, adjusted tx positions slightly to limit tube heat and hum. Then once the final top plate was drilled,it took a couple of hours to finish.
here's my breadboard darling amp.
http://diyparadise.com/rebuiltdarling.jpg
octal relay socket base fits octal tubes perfectly. no need for soldering!
changing caps is just some screws!
DonJuan
http://diyparadise.com/rebuiltdarling.jpg
octal relay socket base fits octal tubes perfectly. no need for soldering!
changing caps is just some screws!
DonJuan
Smart dogs?
Hehehe, Brett , more or less the same situation with my 813s,
the amps are all over the place , the dog never go near it
Those dogs must be smarter than we think 😉
Cheers
Hehehe, Brett , more or less the same situation with my 813s,
the amps are all over the place , the dog never go near it
Those dogs must be smarter than we think 😉
Cheers
Possible solution
Here is another idea.....
Kevin
Here is another idea.....
Kevin
An externally hosted image should be here but it was not working when we last tested it.
Re: Smart dogs?
He's smart, but he's also learnt survival skills living with me for seven years, such as a turbo rotary belches (BIG) flames sometimes, so don't lie behind it.
I decided to have some fun today with the 813PP's, and switch in the different biassing and first cap in the PSU (now CLCLC instead of LCLC) so they're running 900V/110mA instead of 530V/80mA. The 4 of them all lit up like that seem to have a physical presence, almost like a forcefield around them. He stayed even futher back than usual after they were modified. 🙂
I also have some GM70's coming to try in it.
slowmotion said:
Hehehe, Brett , more or less the same situation with my 813s,
the amps are all over the place , the dog never go near it
Those dogs must be smarter than we think 😉
Cheers
He's smart, but he's also learnt survival skills living with me for seven years, such as a turbo rotary belches (BIG) flames sometimes, so don't lie behind it.
I decided to have some fun today with the 813PP's, and switch in the different biassing and first cap in the PSU (now CLCLC instead of LCLC) so they're running 900V/110mA instead of 530V/80mA. The 4 of them all lit up like that seem to have a physical presence, almost like a forcefield around them. He stayed even futher back than usual after they were modified. 🙂
I also have some GM70's coming to try in it.
Re: Breadboards
Craig, every once in a while a real gem comes up, yours is one the most original and neat realizations bar none! It makes me want to get into tubes. What project is it?
On the other hand elan120 has taken the breadboard concept to a very dangerous extreme, I wouldn't recommend that unless you want to die young. Alligator clips do snap off and with 500VDC going around you may have a 'situation' on your hands.
Ryder said:
Craig, every once in a while a real gem comes up, yours is one the most original and neat realizations bar none! It makes me want to get into tubes. What project is it?
On the other hand elan120 has taken the breadboard concept to a very dangerous extreme, I wouldn't recommend that unless you want to die young. Alligator clips do snap off and with 500VDC going around you may have a 'situation' on your hands.
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