DIY AIR BRAKE WITHOUT THE RHEOSTAT?

[Teije]

could anyone please send me a link to the schematic of this airbrake?

my mail is el_teije@hotmail.com

[M Fowler]

https://tubeamparchive.com/viewtopic.php?t=8733

[Rich M]

That Lorlin switch is only rated 150 mA. Isn't that a problem?

Anybody????

[mhuss]

I agree the rating is lightweight, but mine has gotten a fair amount of usages and hasn't melted yet.

If you can find a better 2P6T switch, by all means use it (and share the source and part # with the rest of us!)

--mark

[rooster]

This is my version using a 5 position switch. The switch is like the Lorin but Alpha instead - no idea what the rating is but I assume the same. The switch is unique, it is two pole, yes, but you can change the amount of 'clicks' or positions with a trick washer/latch that is supplied with it. Which means that the same part number is probably sold as many different switches but I haven't really looked at this. From Mouser.

The box is the Hammond cast piece and the resistors are pop riveted in place. The paint is gold Hammerite. The knob is a Gretsch gtr knob but I really want that Qparts gold aluminum pointer knob that costs about $17 delivered. Arrg, can't bring myself to spend the money. Oh well..

Without hesitation, thank you to Ken Fischer for the original design, this Forum for the its 'out in the open' attitude and all the cloners sharing their game. Special thanks to rawnster for letting me use his Blue Box - I am very sure I would not have seen the value in any kind of attenuation device until I used his.

NOTE: THE MIDDLE POSITION IS, AS YET, NOT CONNECTED! SO DON'T BE THROWN BY THE PIC. THE ADJUSTABLE PIECE IS UNAVAILABLE FROM MOUSER AS OF THIS DATE UNTIL SEPTEMBER. ANY HELP OUT THERE??? (I NEED FOUR.) I WILL CHECK WITH SOME LOCAL SUPPLIERS TODAY BUT I AM DOUBTFUL HERE. PORTLAND, I LOVE THIS TOWN, BUT IT AIN'T FAT ON TOO MANY THINGS LIKE THIS, SAD TO SAY.

[Structo]

Very nice Rooster.

I hear you on the availability of parts locally.

We have a Norvac Electronics in Salem but that's about it.

Good place for resistors but beyond that it is hit or miss.

Most their E caps look like they've been on the shelf for 15 years.

They don't sell a lot of those so I'm never real sure of how good they will be.

Thank God for Mouser though, ship fast and have everything. Too bad they aren't cheaper...........

[rosspix]

Rooster,

I saw the clamps were on backorder, but placed my order with Mouser anyway... That was Weds lunchtime (UK) and the *full* order was delivered this morning! It might be worth giving them a call...

Cheers,

Ross.

[rooster]

OK, I will check this out. They may have a different wharehouse for the UK? That's what I think here.

Here's the other unit, BTW. It is going into the speaker cab so it is basically 'open face'. Wait till you see the cab this cat has built for this other Rocket. I will post some pics when he gets it wrapped up.

[rosspix]

Just checked the FedEx manifest: it was ex Fort Worth, TX... You may be in luck

excellent service, and sales tax/duty included.

[rooster]

Hey, those bastards! They are in and were in on the 4th!! ARRG!!!!!! So I ordered a dozen. Man, what a drag, won't ship till Monday and there was nothing else I needed..... Ah, but I will be a patient man here I guess - no options actually. And I am using the gold box, even without the middle position and it works very very well. I am very happy to have such an awsome device, I guess that's the real thing to say. mhuss, Mark, I guess you startted this 'share' post, so let me thank you directly, as well - this is a great tool, no doubt - Thank you!!!

OH - wait a minute - jimi hairless? Who do I thank here for all the original work and trouble shooting?

[MBD115]

Mouser back ordered my clamps also and said they would not ship until Sept but informed me they were shipped earlier today. Should have mine Monday.

I build the one with the rheostat and feel it sucks up too much tone. It quiets the amp down as expected but the final results are not that pleasing to me. I do like the tone from the one clamp I did have (set at 16 ohms). When I get my other clamps in I plan on doing more experimenting but I can't see me using the rheostat much.

[rooster]

Structo - Yeah, Norvac's cousin store is here. Whatever bad things I may say about it, it ain't as bad as nothing at all. Really, I remember when this town was busting with well equipped electronics stores. What has happened? Has the internet really won the electronics supply war? Man, I think it has. What does this say about people like us? How many 20 somethings are building amps? Not many. And hey, why would they when you can buy a Frontman 25 for $130 that is the most incredible doorstop made by man/woman - except its actually too big for even this! Oh well...

So I will wait. I almost hate to say it but the Mouser folks are pretty darn helpful - and phone call business is not my favorite thing. WTF, maybe they have won the war for a good reason.

MBD115 - Yeah, after borrrowing rawnster's blue box I forgot about running a rheostat. Its a ton of dough, too, and clearly I will stay within the first 3 clicks for anything I do. This being said, I ran my BJr at 5 clicks today for fun and it actually sounded very good. Man, the design is way better than any Hot Plate I ever owned, and I have owned 3 for the record. Those things made me swear off such devices. OK, sorry to rant.

[MBD115]

I must say I'm a little afraid of blowing an OT with that rheostat cranked full bore. I do hear a little awful tone in there with it cranked up that I don't like to see. I so feared it that I right away tested the amp without the airbrake at all to make sure I didn't hurt my OT. Gladly it sounded ok as usual.

My little 16 ohm click I have so far (waiting on back ordered parts from mouser) sounds good and does indeed reduce the output volume but not by enough for this crowded RV camper park environment I'm stuck in on this job. I actually need the full blown rheostat for gain control with this Metro JTM45 build, but so far the airbrake thing simply scares me. I can hear it sucking the tone out of my OT when cranked with that rheostat. I'll just play it clean if I haft too until I get my RP-1000 box this weekend.

My needed hardware should be here next week at the latest so then I can test out the other settings.

MD

[gwtekman]

I agree the rating is lightweight, but mine has gotten a fair amount of usages and hasn't melted yet.

If you can find a better 2P6T switch, by all means use it (and share the source and part # with the rest of us!)

--mark

How about this switch from Mcmaster Carr?

http://www.mcmaster.com/#65865k32/=38f3f7

Double Pole 6 14 2.5 amps @ 125 VAC/350 mA @ 125 VDC 0.39" 0.82" 1.03" 0.25" 1.5"

65865K32 $7.45

[eltel]

Hi can anyone give me the mouser part no's needed to build one of these. I'm a newbie to DIY electronics, but have seen this and i've just got to have a go and make one for my 40 watt blues deluxe, which could do with a bit of taming! a friend has an ultimate attenuator which is great but way out of my price range.