Another Breadboard, but slow builder

[Ed_Chambley]

I have been bothering Dave and Pete enough.  It is time to begin.  My board is 38.5 x 25 working area.  Yes, very large, but it will have a control section for 2 autoformers, one for a filiment transformer that will be permanent. First photo here shows the outside frame.  That is all.

[Ed_Chambley]

Next we have a rabbited interior frame with a center rail.  The rabbit will allow for the .25" white acrylic to be mounted to and the center frame is for support.  It also will have a bottom when complete.  The actual size is 1/2 the size of a new workbench.

[Ed_Chambley]

At this point it is 4" tall, but will have 5/8 copper clad bottom.  For the main connections I will be using barrier strips, heavy ones from McMaster Carr.  I now have plenty on DIN rail and Octal Relay sockets, I have 12.


I plan to use Aluminum angle and drill holes to accept the proper size pots and jacks.  Next on the list.  Thanks to Pete, I have a proven size for making 9 pin, 7 pin and sub miniatures with DIN adapters.  The small tubes will be mounted to Red non conductive, G10.  I have plenty of barrier strips in various sizes to insure I get a nice grip on wires and components.


I will not use the entire board for tube amps. I need an area to include a tube tester so I can test and burn in tubes at operating voltages as well as mounting my cap reforming to it as well.


I will have some questions along the way, so please chip in if you will.

[shooter]

Nice!, I did an 8X36 over the winter, it has now got 3 appendages, so Rev2 sometime this year!

[Ed_Chambley]

First Question is for Dummyload Pete.  You mentioned if you were to change anything, that you would have made all your barrier strips horizontal.  Not sure what you meant, so if you see this, please elaborate.


I do plan to use the correct transformers for each circuit, just not for heaters.


Also, how far apart is convenient for mounting the DIN rails.  I am working on a drawing, so I need placement position.  It appears Dummyload has placed the DIN rails and Barrier Blocks 4" apart which makes the barrier centered 2" from the DIN and again 2" from the DIN to the next barrier strip.  Is this spacing needed or could it be a little closer?


This question goes out to others who have built one.  Dave made boards with 3, 9pin sockets on a board and included an area to build a circuit broad in front of tone stack.  And another combined board for a Fender Reverb.  Is there a certain reason to not do this as I was planning 2 small tubes per board and individual octal relay sockets.


I cannot think of anything else, but those who have ran into traps, please let me know so I do not repeat them.


And thank you guys for any help you can provide.  BTW, I have a lot of gauges which I will be adding simply because I have them.  Not a lot, but I do want to monitor the AC from each autoformer.

[Ed_Chambley]

Last thing for tonight.  Something I really do not understand.  When you have 120 VAC providing current to a transformer, how do you determine the proper fuse amp for the DC side?  Normally I see B+ at 500ma fused and anywhere from 1 to 3 amps on the AC side.  Is this simply the total load on the transformer?

[Ed_Chambley]

Nice!, I did an 8X36 over the winter, it has now got 3 appendages, so Rev2 sometime this year!

This is actually going to be 1/2 of the top of my new workbench.  This is my 4th workbench.  Maybe this time I can make it comfortable.  Here is hoping!

[Willabe]

 

[SILVERGUN]

Last thing for tonight.  Something I really do not understand.  When you have 120 VAC providing current to a transformer, how do you determine the proper fuse amp for the DC side?  Normally I see B+ at 500ma fused and anywhere from 1 to 3 amps on the AC side.  Is this simply the total load on the transformer?

Yes. On the primary input side, the current draw is proportional to the output of the amp, plus any filaments incl. tube rectifier draw.
That's why you'll see a 5 watt (SS rectified- Champ 2) with a 1 amp fuse while a tube rectified Champ will have a 2 amp'er. (they weren't really using 'exact' math)
SS rectified Twin Reverb AB763 (4- 6L6) has 2.5 amp, tube rectified Super Reverb AB763 (2- 6L6) has a 2 amp.
Jimbo's rig = 10 amp'er (for 4 KT88) - so it would essentially catch fire before popping that fuse, and has...
 
Remember, that if you are using a separate filament transformer, your primary draw will go down, and fuse accordingly.
 
On the B+ side, yes, you are protecting your OT from excessive current draw in the event of a tube short, etc....
Find out what the max. mA rating is for your OT , round up heavy, and fuse accordingly. Only problem there is when you're pushing it, you WILL exceed the max. ratings, and have to replace a fuse (if you didn't round up heavy enough)
Jimbo would just put in some tin foil.
Mr. Soldano went with 1 amp on the SLO100, knowing his amps would be overdriven hard
 

[SILVERGUN]

Just for the record...
I like the removable aspect (mounted on standoffs) of this front board because I can take it off and populate it like an actual board layout while I'm sitting at my desk or couch, and not tied to the workbench in front of the board....basically, a bonus because my bench stool is not all that comfortable.
 
 

[SILVERGUN]

Back to fusing...
Another good option is to fuse the secondaries of the main transformer winding BEFORE the rectifier.
Merlin covers all of this very well:
http://www.valvewizard.co.uk/fuses.html

[sluckey]

I would not use fuses on a breadboard. I'd use circuit breakers instead. Weber has a good selection and cheap prices...

     https://www.tedweber.com/amps/fuses-circuit-breakers

[SILVERGUN]

Yeah, what he said..
..except, I don't love the DC V ratings on those, so watch where you put em

[John]

because my bench stool

Seriously? You sit down?

[Ed_Chambley]

I will be using breakers.  I was asking simply for the understanding of how to calculate what I need.  I also use smaller fuses.  Like my Super Reverbs, I use  1 amp fast blow.  Never have a problem.


There is an electronics store downtown called ACK who provide a lot of items to the Hammond Organ Repair Guys as well as HiFi.  They have flip style breakers starting at 200ma and go up to where you have to go the an electrical supply to get something bigger.


Everything except Octals will be attached to DIN rail mounting adapters, but I have not decided to make one socket per board.  Also, since I really do like Octal preamp tubes I will make some of these as well.  Save the Octal Relay sockets for the power section.


I do not see any benefit in making a dual 7 pin board or a dual subminiature, but I can see value in making a longer 9 pin board with 2 to 3 sockets, maybe one that can hold a revibe circuit, but the 6V6 verb is an absolute.  I also really like Supro Tremolo, but it is easy.  I have always wondered how the revibe would sound if inserted after the preamp.  We will find out.


I will bump this occasionally to share where I am.  I am not in a hurry.


Thanks for the comments guys and feel free to add what you would want.  I certainly cannot think of everything.

[Ed_Chambley]

Just for the record...
I like the removable aspect (mounted on standoffs) of this front board because I can take it off and populate it like an actual board layout while I'm sitting at my desk or couch, and not tied to the workbench in front of the board....basically, a bonus because my bench stool is not all that comfortable.

yep, I can see you sitting watching TV with a table full of Orange Drops.


The DIN rail mounts I found are easy to remove and stand up nicely similar to standoffs.  I see the benefit.  My biggest chore is construction.  Did I mention I was remodeling my lower level, some would call it a basement, but it is really not.  I am removing steel poles and replacing them with a Laminated Beam and completely remodling a full bath while building racks for test equipment.


Like I said, it will be a little while coming, but I have never had a proper layout.  This time I am removing everything and placing all my electronic gear in a room I have framed.  Looking at all of it will really let you know what you need to build.

[Tone Junkie]

Ed I went and made up some modules like different power and pre amp sockets.Some with room for a rectifier tube and some without . so I could mix and match.
Bill 

[Ed_Chambley]

Thanks for the input.  Couple more, not much to look at, but progress.  Waiting for a couple things, but so far it is going better than I expected.

[DummyLoad]

at least it's moving closer to being finished. 


--pete

[Tone Junkie]

Ed I really like the thought of a cap former and a tube burn in section all bases covered.
Bill

[Ed_Chambley]

Thanks for the input Bill. I had planned to put my cap former on it, but did not think of burn in since I have so many tubes stashed, but I do re tube others amps and that would be nice.


Actually 2 parts now are placeholders. What is the most time consuming is making the actual socket stands, but a lot of that is me.


Yes, closer to completion. Then I can test tv tubes for tone. Actually it is a great learning process.

[Ed_Chambley]

More Progress

[Ed_Chambley]

Again.  Just in case someone may wonder. this transformer has 2, 5 amp 6.3 volt for heaters.  10 amps in all and is a permanent transformer for the board.  The brackets are to mount the actual transformer that will be used.  I will have a transformer to elevate heaters and I have some 200 ohm 5 watt pots for balance.


The board should be able to run 3 designs at once, the idea is to be able to switch circuits or preamps as well as power sections.  Also, the 2 Staco Variacs are individual control of filaments and separate plates.


the 2 switches are each for 1 heater run each.  More to come later.  Suggestions welcome.  Next step I am making small tube stands for the DIN rails.  I plan use euro barrier strips and I have a good supply of Potter Relay Octal.

[Willabe]

Looking good Ed!   

[kagliostro]

 

[Ed_Chambley]

Thanks guys.  I will keep chugging along, but I did want to be better about showing what I am doing.  It is helping me to design this thing, hopefully it will help someone else.

[SILVERGUN]

The board should be able to run 3 designs at once, the idea is to be able to switch circuits or preamps as well as power sections.

Whaaaat???
And not have to build 3 boards?
Well that's no fun.
 
"Tricked out"....as my hotrod building brother would say
 
Next, I'd love to see a 12 speaker-switching-matrix wall.
AES had a 4x12 at the NY amp show a couple years back loaded with 4 different Jensens....ran it with a rotary selector switch....been in my head ever since.
 
Press on young man...there's still time!

[Tone Junkie]

Looks awesome Ed.
I miss understood. I thought you had said you were putting a cap former and tube burn in station on board. I really like what you have going .
Bill

[Ed_Chambley]

Looks awesome Ed.
I miss understood. I thought you had said you were putting a cap former and tube burn in station on board. I really like what you have going .
Bill

I am going to do this as well, or plan to.  I am building a DIN board just for this and it will hold 6 Octals and 6, 9 pin.  I will have test points for the tubes, but I do to plan to start selling tubes so I do not need a lot of room for this.  I couldn't be a tube seller because I cannot seem to sell any anyway.


It will be to the right front, but the cap former you will see when I actually cut holes for cap cans and the cap former will provide the power section filtration so it will have dual duty.  I really don't think burning in tubes and forming caps while testing a circuit is a good plan so I am trying to incorporate as much functionality as possible.


I really liked Silvergun's Reverb Board, but I will not need it all the time.  To burn and test tubes, I will use the same idea.


really, I am doing more than it looks, it is just I am having to split up my time.  For instance, I am looking for 2 drawer units.  I want 12" wide and 32 to 36" tall.  These will be the legs of the new workbench and I also finished a new dedicated 20 AMP AC run from the panel using shielded romex.


That is why I titled this as "slow Builder," as it looks this way.

[Ed_Chambley]

Well guys I have a few moore photos of breadboard building.  I believe all my parts to complete are in hand.  Ths is just a coule of photos of the underside.  Now I will be able to start wth a circuit assembly. yu can see 2 autoformers, 2 VAC guages.  There is also 2 toggle breakers, one for each filiment string.  One main 3 amp breaker.


I have decided to use an isolation transformer to build a bias supply, or better said 4 individual bias adjustments and 2 with adjust/balance for HiFi needs.


As the 10 amp 6.3 filment transformer (2 @ 5 amps each) has no center taps, I have 2, 220 ohm wirewound pots for a center tap and and 2 connection points for heater elevation.  60-80 vdc is what I have used with good sucess when quieting down old amps.


I am thinking for a rectifier board I will have a 25 watt bridge, a full wave and 3 tube sockets, 2 octals and a 9 pin.  If I am missing somethng here, please reply with thoughts.

[Ed_Chambley]

and my new workbench, well part of it.  Now with tools. I finally sprung for some Kline tools.  Yes, they are overpriced, but they sure are sexy.


They sell screwdrivers made for the various size barrier strips and fit perfectly.  This is Silverguns fault as he told me having th right screwdriver for the barrier strips is important as to not strip the heads of the screws.


There is much more to this workstation, but rght now I am sorting testing and boxing tubes, the heavy lifting and remodling structure is in-place.  I am finally to the finishng point.

[John]

Looking good! I think before I tackle another project, organizing the milk house and maybe making a better bench is on the list.

[SILVERGUN]

 
Nice monitor!
 
Having the right monitor for your old eyes is important too, but I didn't need to tell you that

[Ed_Chambley]

Nice monitor!
 
Having the right monitor for your old eyes is important too, but I didn't need to tell you that

No argument here. I got 2 of these LG 40 inch smartass tv's for 300. Brand new in box from Best Buy just by walking in. The manager picked out me for a manager's special. I was the 100,000th customer to buy something at the Waynesville North Carollina store. 60 percent off my next purchase. Bet they still made some money.

[purpletele]

^^^^Good story on the monitors.

Nice shop and set of tools!

[Ed_Chambley]

^^^^Good story on the monitors.

Nice shop and set of tools!

Thanks purple. Wait a bit and I will get some showing everything. I am very pleased finally. This is actually my 5th attempt. I had said 3rd, but truthfully it took more to learn what is convenient and not.


Also, the chair for an old guy of 53, yea to some is a pup, has been great. It lifts from 23 inches to  31 or something. The arms lift too which is nice because when I got bit by the valve fever I made a promise to myself if I spend an hour with electronics I would play at least the same if not more.


So far guitar time is double electronics time, but really equal if you consider study and forum time.


Time to jam.