Search found 115 matches

by xk49w
Fri Mar 13, 2015 7:02 pm
Forum: Technical Discussion
Topic: Thoughts on cathode current sensors
Replies: 20
Views: 3088

Re: Thoughts on cathode current sensors

I have some Littelfuse 2AG (5x15mm) axial through-hole fuses I was intending to place in series with each leg in the rectifier chain. They should never blow in normal operation. If they do the amp would require servicing. Of course, without them it would require servicing also, only for more $$ if a...
by xk49w
Tue Mar 03, 2015 1:38 am
Forum: Dumble Files
Topic: 3rd Generation Period Correct ODS 50W
Replies: 41
Views: 52294

Re: 3rd Generation Period Correct ODS 50W

I am now starting to attach wires to the assembled boards based on this layout and this schematic (both in this thread). I sort of expect that the layout is correct. That said. the schematic appears to have some small errors. The two tube sections are reversed for V1 and V2. Maybe this doesn't matte...
by xk49w
Fri Feb 27, 2015 2:34 am
Forum: Technical Discussion
Topic: Edcor service
Replies: 24
Views: 4455

Re: Edcor service

I have bought four with no issues. I would pay more if they were physically more rugged and would prefer them to be so.
by xk49w
Wed Feb 25, 2015 1:17 am
Forum: Dumble Discussion
Topic: New Build D-lite 22.... where to source chassis and boards?
Replies: 6
Views: 1730

Re: New Build D-lite 22.... where to source chassis and boards?

I see the Brown Note amps website has been updated 2015 and includes a lot of new amps/options I have not seen before but the forum is down. So that must mean these guys are getting their kits or able to order them? A month ago or so I inquired and had some email back-and-forth about a chassis and ...
by xk49w
Tue Feb 24, 2015 5:26 pm
Forum: Dumble Discussion
Topic: 3rd Gen w/PAB
Replies: 6
Views: 1796

Re: 3rd Gen w/PAB

I just did something similar with a 2nd gen. Obviously a jumble of several eras but it works. I do PABs with a tail resistor rather than the lift (little blue 10-turn on the relay board). You'll have your own opinions there That's interesting. And it appears to remove a bit of the the load on V1 ca...
by xk49w
Tue Feb 24, 2015 12:44 am
Forum: Dumble Discussion
Topic: 3rd Gen w/PAB
Replies: 6
Views: 1796

3rd Gen w/PAB

I am planning a 3rd Gen into a cepedals chassis and want to use the PAB feature. I hadn't seen one of these so I sort blended a couple of schem's and had at it. It seems pretty similar to the #124 schematic but R25 connects to S2A rather than S2 common, which seems to be a standard connection for PA...
by xk49w
Mon Feb 16, 2015 5:57 pm
Forum: Technical Discussion
Topic: Incandescent light bulbs and Ohm's law
Replies: 17
Views: 2358

Re: Incandescent light bulbs and Ohm's law

Leslie 122 reverb amp uses incandescent to limit drive into the tank, paralleled with a 16 ohm speaker voice coil. Light leaks from under the chassis when cranking it!
by xk49w
Mon Feb 16, 2015 5:05 pm
Forum: Technical Discussion
Topic: Polyfuse/ polyswitch to prevent tubes from redplating.
Replies: 8
Views: 1869

Re: Polyfuse/ polyswitch to prevent tubes from redplating.

R.G. wrote:Come to think of it, why *don't* I go make these to sell?? :lol:
PIC12F1571 for example, 8 pins, four 10-bit ADCs, 1.75 kbytes pgm, 128 bytes RAM, 128 bytes EE, internal oscillator, $0.66 in singles.
by xk49w
Fri Feb 13, 2015 3:20 pm
Forum: Technical Discussion
Topic: Fender Style Mosfet Reverb Board
Replies: 16
Views: 5551

Re: Fender Style Mosfet Reverb Board

Mosfets do sound very tube like! but for this I do not like the greater frequency range they drive the pan with, I like the sound of that small OT rolling off the bottom and top range like it does for the most part! It does use a conventional reverb transformer so there will be some bandwidth limit...
by xk49w
Wed Feb 11, 2015 1:49 pm
Forum: Dumble Discussion
Topic: Radio Shack 273-1365 xfmr
Replies: 7
Views: 1977

Re: Radio Shack 273-1365 xfmr

Today it is back on sale online.
by xk49w
Tue Feb 10, 2015 1:13 am
Forum: Dumble Discussion
Topic: Radio Shack 273-1365 xfmr
Replies: 7
Views: 1977

Radio Shack 273-1365 xfmr

RadioShack is bankrupt. Yesterday the 273-1365 transformer, commonly used as a relay supply transformer was on sale on line for $4.99. Today they were all gone. I found two at a local store and bought one. The other was a staple-up return package and looked dodgy. Maybe I should go back and buy it a...
by xk49w
Sat Jan 10, 2015 9:25 pm
Forum: Technical Discussion
Topic: Anybody try "Manhattan Style" construction?
Replies: 19
Views: 3966

Re: Anybody try "Manhattan Style" construction?

Back in the day we used to call that "dead bug". I've made a lot of brassboard circuits of RF/IF, even high-speed digital stuff that way up to 200-300 MHz. Short leads, good grounding. Solder up a G10 box on top, paint it, done.
by xk49w
Fri Jan 09, 2015 10:12 pm
Forum: Dumble Discussion
Topic: Bezel for CE Chassis
Replies: 11
Views: 1959

Re: Bezel for CE Chassis

I just got a CE chassis today. Very nice. This indicator also is .3125 dia. (5V incandescent) https://www.alliedelec.com/search/productdetail.aspx?SKU=70152565#tab=specs Pricey though, lens and bulb extra. [img:400:267]https://lh6.googleusercontent.com/-UanL1JOhcrk/VLBSB2b2HwI/AAAAAAAAEkw/ZeajXEzfhV...
by xk49w
Sat Oct 05, 2013 8:39 pm
Forum: Technical Discussion
Topic: Advantages of PTP wiring?
Replies: 54
Views: 12302

Re: Advantages of PTP wiring?

teemuk wrote:
here Is a nice way to use different construction methods Tone King Amplifier
Looks nice but I would hate to repair that.
Comment on the FB link say it sits on top of the tube socket but I can't see how it connects to the socket from the picture.