Author Topic: Relay Board idea (Read 22839 times)

kagliostro · « **Reply #50 on:** October 07, 2012, 01:48:42 pm »

Yes that was what I was thinking

K

p.s.: may be you can move the optional cap holes more near to the regulator, so you can mount it also if an axial principal cap is mounted

Willabe · « **Reply #51 on:** October 07, 2012, 02:37:42 pm »

PSU board looks great. Agree, smart to keep PSU and relay boards separate to keep ac by the PT and power cord/switch/fuse.

I like the radials they have now, size, spec. and price wise. ($0.02, drop the big axial cap option and shrink the PSU board a little more.)

Brad

EL34 · « **Reply #52 on:** October 08, 2012, 06:58:27 am »

Just re-stocked the bin full of 4700uf/16v caps, so I would like to use them up

The board is only 2 inches long, which is tiny
And it's only 1.5" tall which will fit on the sides of Fender chassis

I don't really think a cap on the output is needed, but the option is there
A radial is the only thing that would fit on the tiny layout.

If you really want to use an axial on the output you can stack it on top of the big axial.

Here's what Andy at Mojo drew up

Willabe · « **Reply #53 on:** October 08, 2012, 08:17:11 am »

Quote from: EL34 on October 08, 2012, 06:58:27 am

Just re-stocked the bin full of 4700uf/16v caps, so I would like to use them up

The board is only 2 inches long, which is tiny
And it's only 1.5" tall which will fit on the sides of Fender chassis

Understood and agree, it's plenty small as is.

Andys drawing looks good too. Still think the relay boards should be singles, but you can have them made where they score them so they are doubles that break apart into singles.

Brad

EL34 · « **Reply #54 on:** October 08, 2012, 08:25:25 am »

Andy just emailed me
You got your wish

He has to make them as singles for some of his amps he makes
And he gets a better price break on singles because the quantity would be higher
It does make more sense to have singles
4 relays in an amp like on the D'mars are not that common

He also figured out a way to get the optional cap on the same board even if you use an axial for the main cap

He is mailing me a couple laser cut test pieces so I can make sure all the parts I stock fit properly

I will probably go ahead and stock both the radial caps, besides the axial I already stock

Willabe · « **Reply #55 on:** October 08, 2012, 11:23:04 am »

Very nice Doug!

Looking forward to buying a few for a new build to try them out.

Brad

navdave · « **Reply #56 on:** October 10, 2012, 01:07:59 am »

Anyway you could make these into two individual units?

Tone Junkie · « **Reply #57 on:** October 10, 2012, 01:41:50 am »

Doug do you have any of the doubles left if Im not mistaken 1 page back you said something like you had 7 left and i think you mentioned a price I would take 5 right know if you have them .
once you have the details worked out and in stock I look forward to some singles and power boards.
Thanks Bill

Willabe · « **Reply #58 on:** October 10, 2012, 02:35:56 am »

Quote from: navdave on October 10, 2012, 01:07:59 am

Anyway you could make these into two individual units?

Huh? Read the _WHOLE_ post.

The PSU board will be 1 individual unit and the relay board will be 1 individual board per relay.

Brad

navdave · « **Reply #59 on:** October 10, 2012, 03:00:15 am »

Not talking about the relay power supply. Talking about the relays themselves.
Every pic I've seen shows two relays on one board together. I have needs for two
relays in two separate places. One relay in the preamp one by the power amp.

Quote from: Willabe on October 10, 2012, 02:35:56 am

Quote from: navdave on October 10, 2012, 01:07:59 am
Anyway you could make these into two individual units?

Huh? Read the _WHOLE_ post.

The PSU board will be 1 individual unit and the relay board will be 1 individual board per relay.

Brad

John · « **Reply #60 on:** October 10, 2012, 05:50:22 am »

Quote

Andy just emailed me
You got your wish

He has to make them as singles for some of his amps he makes
And he gets a better price break on singles because the quantity would be higher

But you're right, everywhere else they were talking about the double relay board. And I was thinking "gee, I wish they'd make them as singles"

EL34 · « **Reply #61 on:** October 10, 2012, 06:37:58 am »

The relay boards will be singles.

I have 8 of the doubles left
Jeff is the only one that spoke up for two of them

Just add a note to your order that you want a double relay board

The sample laser cut boards from Mojo should be here today for me to ok

Willabe · « **Reply #62 on:** October 10, 2012, 02:53:58 pm »

Quote from: navdave on October 10, 2012, 03:00:15 am

Every pic I've seen shows two relays on one board together.

Sorry Dave, yes your right all the pics show doubles.

But things changed later as the guys pointed out.

Brad

EL34 · « **Reply #63 on:** October 11, 2012, 02:37:42 pm »

I got the laser cut boards from Andy at Mojo today

The boards are cut to make sure all the parts fit as I designed them to
He just uses some black board material, it's not pc board material

There's a couple things I need him to correct and then we are good to go.
The relay board was only .75 inches wide.
It was supposed to be .9 inches wide so that you had room enough to wrap wires around the turret lugs.
So I am having him re-do the width on the relay board to .9 inches

I am having him move the Ac lugs on the power supply board farther away from the bridge
One lug is really close to one of the Ac holes

Here's a shot with the laser cut boards and parts added

EL34 · « **Reply #64 on:** October 12, 2012, 12:43:20 pm »

Here's Andy's updated drawing after fixing a few things

He re-did the bridge area so that you can use stand alone diodes or a BR305 bridge

gar13 · « **Reply #65 on:** October 12, 2012, 02:17:43 pm »

To me, it looks like there is only enough room to wrap wire on the top row on the relay board now, bottom row looks like same spacing as the test piece....

EL34 · « **Reply #66 on:** October 12, 2012, 02:31:37 pm »

Not sure what you are saying, here's shot of my prototype board
Plenty of room to wrap around the lugs

The production boards will have the same spacing as my prototype board

gar13 · « **Reply #67 on:** October 12, 2012, 02:34:01 pm »

Sorry, I was looking at Andy's drawing and sample boards, not your prototype. It looks like the top row of turrets have more space than the bottom row. Looking at your prototype, maybe that is intended. Sorry for being confusing.

EL34 · « **Reply #68 on:** October 12, 2012, 02:41:24 pm »

If you mean Andy's black boards shown a couple post up, the text below those boards explains that he made the relay board too thin at .75 inches
It was supposed to be .9 inches, just like my prototype

That has been fixed

tubenit · « **Reply #69 on:** October 14, 2012, 03:07:57 pm »

I have continued to update the ARCHIVES information on relay switching. Doug's new relays should work perfect for this.

I've included some new photos & illustrations in an effort to make this even easier those who wish to try it.

http://www.el34world.com/Forum/index.php?topic=14348.0

With respect, Tubenit

EL34 · « **Reply #70 on:** October 14, 2012, 06:09:41 pm »

Thanks for all the info updates Jeff

tubenit · « **Reply #71 on:** October 16, 2012, 06:34:03 pm »

Guys,

I got two of Doug's prototype relay boards. Man, these are VERY nice boards! Very neat layout and very very compact.

More impressive in person than in the photo that Doug posted. These will be very easy to place between pots and turret board and
super easy to solder wires into.

Nice job, Doug!! I like these quite a bit better than the ones I built for myself.

With respect, Tubenit

EL34 · « **Reply #72 on:** October 16, 2012, 06:46:30 pm »

Thanks
Those are my homebrew CNC prototypes
There won't be any more of those
But, the production ones will be even nicer because they will have through hole solder pads on both sides of the board

The same with the relay power supply boards.

You got two of the 10 boards I made
Another customer bought the other 8 of them
So they are all gone until the production boards get here which should be 2-3 weeks from now

tubenit · « **Reply #73 on:** October 16, 2012, 07:40:28 pm »

I think these are probably compact & narrow enough to work well with a Tweed style chassis which is what I plan on using a pair for. So, I'll give an update hopefully within the next two weeks on how well that works out.

Tubenit

EL34 · « **Reply #74 on:** October 17, 2012, 07:06:14 am »

ok thanks

MFowler · « **Reply #75 on:** October 18, 2012, 02:44:05 pm »

Looking forward to buying some of these relay boards for many projects, Thanks.

Mark

tubenit · « **Reply #76 on:** October 22, 2012, 07:46:57 pm »

OK, I installed two of the relay boards into my Tweed BluezMeister amp.

Now, the TBM is in a 18.5" X 6.5" X 2.5" 18 watt style open end chassis. I actually cut the 20" length down to 18.5"

This amp combo is about the size of a 5E3 combo amp.

However, it has clean/OD, PAB, & midboost. The clean/OD and midboost are relay switched using a foot switch box.

It also has on board an active FX loop. I left out the LNFB around the 2nd triode and I changed some of the component values.

What I am trying to do is convey that I have ALOT going on in a very small chassis ............ AND the relay boards are super quiet.
They were very very easy to wire up and I actually built a relay power supply board that I mounted on L brackets on the side of the amp.

The combo amp is so quiet at idle that I can almost not hear it & yet when I hit a chord, it's VERY LOUD with 6L6's in it.
I think it would be easy to walk into a room with the amp on and perhaps not hear it at all with it on either clean or OD? This is maybe the most quiet combo amp I've owned. It is actually quieter than the D'Mars ODS which has surprised me.

I might add that the previous W____r relay board left me with some hum on the clean channel. Hoffman's relay boards (2 of them) seem to be quieter than the previous 1 relay board. Perhaps I did a better job wiring up the amp??? However, I added an entire FX loop section so the amp chassis is even more crowded with wiring and still quieter than it was.

Very big thumbs up on Doug's relay boards!!!!!

With respect, Tubenit

EL34 · « **Reply #77 on:** October 23, 2012, 07:32:42 am »

Thanks Jeff
I'll keep you guys posted when they arrive here

Hopefully by the end of this month

navdave · « **Reply #78 on:** October 27, 2012, 02:51:42 pm »

I was looking at your pic of the relay power supply. So you leave your relay power supply floating not grounding it to the chassis?

Quote from: tubenit on October 07, 2012, 07:12:25 am

EL34,

PLEASE don't throw any sharp or heavy objects at my head ..................................

Any chance that you'd be willing to carry a relay power supply board also ??? Since this would be all turrets, the normal board material could be used.

I built mine with an extra 330uf cap that was probably not needed at all?

I'm thinking that "option 1" would be the best since it would maintain the narrow width that the relay boards had?

In the attached photo, the relay power board I built works fine with the D'Mars ODS but would be too wide to use in my Tweed BluezMeister that has a narrower "tweed style 18w chassis".

AND if you're not interested in carrying a relay power board punched out with turret holes, we can easily build our own.

With respect, Tubenit

EL34 · « **Reply #79 on:** October 27, 2012, 03:13:32 pm »

The relay power supply does not use the chassis as the DC ground

It is creating a 5 volt DC supply only for the relay coils
You can think of the 5 volt supply as if it were a separate 5 volt DC battery

navdave · « **Reply #80 on:** October 27, 2012, 06:26:51 pm »

Thanks for the clarification EL34 the reason I asked is because I'm having grounding problems on one of my builds. If I'm not touching the strings this amp has a very audible buzz also shocks me when singing through a mic. I've check and check for a ground loop but I can't find it. I've re-grounded everything twice so far so the hunt is on...

Willabe · « **Reply #81 on:** October 27, 2012, 07:06:03 pm »

Every guitar and amp I ever played through buzzed (with the guitars volume up) when not touching the strings.

Guitars run a wire to the bridge so it's in contact with the strings, which runs back the the amps ground through the guitar cords shield. IIRC it's the players body capacitance that stops the buzz?

As far as getting a shock when playing and touching a mic somethings not grounded correctly. Do both the guitar amp and mic amp have a 3 wire power cord with the 3'rd wire (safety ground) conected to the chassis?

I've kissed a few mics while singing on stage and it's no fun.

Brad

PRR · « **Reply #82 on:** October 27, 2012, 08:55:20 pm »

> audible buzz also shocks me

Input jack MUST connect (usually through chassis) to Wall-plug ground pin.

Somehow it isn't.

> the players body capacitance that stops the buzz?

The player, standing in a room not connected to anything, picks-up a buzz from all the power-wiring in the room. This CAUSES the buzz. When player is connected (through finger-touch) to the same ground as the amplifier input, buzz is much-much less.

It might also help to line guitar wire pot switch jack cavities with metal foil tied to jack ground, ground all non-live metal parts, and use shielded wire for anything more than an inch or so long.

You can't block ALL buzz. The pickup coils must "see" the strings through the poles, and most easy electrostatic shields will muffle the string tone.

Willabe · « **Reply #83 on:** October 28, 2012, 01:28:04 pm »

Quote from: PRR on October 27, 2012, 08:55:20 pm

The player, standing in a room not connected to anything, picks-up a buzz from all the power-wiring in the room. This CAUSES the buzz. When player is connected (through finger-touch) to the same ground as the amplifier input, buzz is much-much less.

Ohhh. OK, thanks PRR.

Brad

navdave · « **Reply #84 on:** October 28, 2012, 06:29:08 pm »

I have a wall socket tester plug tests good. And the really strange thing is that if I touch the bass players bass while also touching my guitar I get a really loud buzz. I've built 5 amps and this is the only problem child.

Quote from: PRR on October 27, 2012, 08:55:20 pm

> audible buzz also shocks me

Input jack MUST connect (usually through chassis) to Wall-plug ground pin.

Somehow it isn't.

> the players body capacitance that stops the buzz?

The player, standing in a room not connected to anything, picks-up a buzz from all the power-wiring in the room. This CAUSES the buzz. When player is connected (through finger-touch) to the same ground as the amplifier input, buzz is much-much less.

It might also help to line guitar wire pot switch jack cavities with metal foil tied to jack ground, ground all non-live metal parts, and use shielded wire for anything more than an inch or so long.

You can't block ALL buzz. The pickup coils must "see" the strings through the poles, and most easy electrostatic shields will muffle the string tone.

sluckey · « **Reply #85 on:** October 28, 2012, 07:16:57 pm »

Check for zero ohms resistance between amp chassis and round ground pin in the AC plug.

navdave · « **Reply #86 on:** October 29, 2012, 03:44:48 am »

Will do.

Quote from: sluckey on October 28, 2012, 07:16:57 pm

Check for zero ohms resistance between amp chassis and round ground pin in the AC plug.

Tone Junkie · « **Reply #87 on:** October 29, 2012, 01:32:04 pm »

Steve what ohm rating would we be looking for I work on planes and when were are checking grounds were looking on a high rating for 500 milli ohms or .5ohms at the highest.
in more critical areas it's lower than that.
Thanks Bill

PRR · « **Reply #88 on:** October 30, 2012, 01:36:54 am »

> what ohm rating would we be looking for

For diverting buzz, many ohms can be acceptable. In the old hot-chassic days we sometimes used about 50K (at 60Hz) capacitive impedance (a compromise between buzz and shock).

A chassis ground SHOULD blow a fuse if the chassis gets straight 120V. This means 120V/20A or under 6 ohms.

Any decent wire and bolt should read well under 1 ohm, below the bottom of standard bench meters. Usually "it is or it isn't", meaning <1 ohm or just plain bad.

I think if the guitar-jack to wall-plug reads within a part-ohm of what the meter says with probes shorted, that's fine.

> I work on planes ...0.5ohms at the highest.

Planes may be more fussy; also planes are built with many sheets of Aluminum riveted together. Aluminum is prone to oxide (especially when flown in damp air) and not-great electrical contact.

navdave · « **Reply #89 on:** October 30, 2012, 03:54:34 pm »

Well I finally found the source of the BUZZ!! I was playing the amp upside down and low and behold no BUZZ... I turn the amp over right side up and the buzz came back so I wiggled the power cord around and sure enogh the cord has a short right at the strain relief. The funny thing is that I tested the groung wire for continuity as well as resistance and both test were fine. Resistance between the plug tip and chassis ground point was 0.5 ohms but when the cord wiggled a certan way it was enough to break ground. Glad I have a 12' cord I got from Doug that I can spare a foot from... Thank you Sluckey and PRR for all the help!

Quote from: navdave on October 29, 2012, 03:44:48 am

Will do.

Quote from: sluckey on October 28, 2012, 07:16:57 pm
Check for zero ohms resistance between amp chassis and round ground pin in the AC plug.

EL34 · « **Reply #90 on:** November 05, 2012, 02:37:49 pm »

relay boards are here, see this post

http://www.el34world.com/Forum/index.php?topic=14598.new#new

Willabe · « **Reply #91 on:** November 05, 2012, 05:12:42 pm »

Just ordered 4 single relay boards and 2 relay power boards + parts to mount/fill them.

Thanks Doug.

Brad

echuta13 · « **Reply #92 on:** November 05, 2012, 07:08:06 pm »

I put in an order for 6 of each. Not sure how long he'll have these in stock.

tubenit · « **Reply #93 on:** November 05, 2012, 08:19:43 pm »

Man, those look FANTASTIC!!!!!

Super super nice design! I like 'em!

Can you please give the dimensions for the relay power supply board? Thanks!

With respect, Tubenit

EL34 · « **Reply #94 on:** November 06, 2012, 05:41:25 am »

Thanks guys, I replied here in the new relay topic
Board sizes added to catalog descriptions

http://www.el34world.com/Forum/index.php?topic=14598.msg139084#msg139084

tubenit · « **Reply #95 on:** November 06, 2012, 10:38:19 am »

Quote

Board sizes added to catalog descriptions

Sizes are excellent!

THANK you! With respect, Tubenit

Willabe · « **Reply #96 on:** November 06, 2012, 10:43:19 am »

Just noticed something.

The boards each have a square through hole pad (or 2) on them. Is that for marking a ground connection?

Brad

EL34 · « **Reply #97 on:** November 06, 2012, 11:54:44 am »

Please use the new relay post at the top of the board for questions on the relay boards

Willabe · « **Reply #98 on:** November 06, 2012, 01:26:44 pm »

OK will do, sorry.

Brad

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Author Topic: Relay Board idea (Read 22839 times)