DRB- box metal work

[N3DRB The Derb]

We got rid of the ugly coax holes. Since we cant handle anything more than a dremel, everything you see was done freehand. We'll have pictures of the front and top soon. All those holes are gone too. It should be ready for paint in a week or so.

The last thing is mounting the new input coil supports provided by JN ( and these wont break ) and drilling the holes and winding the coil. I'll take some internal shots after that.

[w4bfs]

good looking metal work .... I hope the copper theives leave your grounding intact ... I considered adding input taps and series variable cap to mine ... decided to use ext input L network ... 73...John

[KB5MD]

Now, that looks quite nice!  Really, clean and neat.

[flintstone mop]

You haven't lost your touch OM. Believe me, the chemo or whatever drugs you're using makes the hands tremble and you can't do SHuT with tools, can't think clearly, can't dream, can't push the bush, nuthin'!!!!. Everyone's different, that was my experience. It was that way for me for up to 1 yr after the last Chemo treatment.
Phred

[ka3zlr]

Comen right along Derb.. FBOM....

[N3DRB The Derb]

Phred,

the more work I do, the better my left side gets. I have to know when to stop, but my endurance is increasing as well. I can work for 4 hours at a time now most days.

[N3DRB The Derb]

I considered adding input taps and series variable cap to mine ...

I am going to add those as well as make it go on 160. but I need a few more junkbox parts from 2 or 3 more hamfests to do it. I need another one to make my pair of everything as well - pair of matching everything so if I have a crapout or I get worse instead of better i dont have to worry about staying on the air. In the meantime, I'll use it as is. the coil supports are ready, have to epoxy them in place. pix soon.

[WA5VQM]

Man, that's looking good. Clean.
 73, Mark

[N3DRB The Derb]

teh new front of the box. still needs control holes drilled and the swr meter hole drilled. I haven't decided yet which way I will go, use rivets for the small holes you see screws in now and paint over them or use decorative chrome or brass rosette screws after wrinkle is applied.

Any advice? I am leaning towards the screws. The rivet surfaces are pretty smooth, but it may show up.
The epoxy will be cured tomorrow. Then I can wind a new and betta input coil that wont go BOING. 

[N3DRB The Derb]

one of the nylon coil supports broke off - does Epoxy stick to rough sandpapered nylon? I thought using epoxy would b foolproof. 

I re papered it and re stuck it on. We'll see in the morning if it took this time.

[The Slab Bacon]

Nylon is pretty difficult stuff to glue. It is naturally kinda slippery and nothing that I know of sticks to it well. You are prolly better off drilling it and attaching it with screws. I know that you can get nylon screws from most electronic supply houses if you need the extra insulation. I'll have to look real hard, I may still have some at home, or they might have some of them at one of the large "hardware" chains.

                                                      The Slab Bacon.

Timmy, since Gonset #1 is still sitting on my coffee table, do you want me to bring it to How-Cow on Sunday?? Let me know.

[N3DRB The Derb]

Yeah, go head and bring it. I'm convinced these amps have a design problem after seeing #2 but I think I can lick it. I got nothing but time  at the moment and you got your mom and a job + life to deal with. I gotta start dealing and fixing like the Derb of old and handle my own problems. Bring it and we'll get to it after the match box is done. I'm convinced the problem is parasitics caused by the mechanical design. A grid dip meter will tell the the story. I may very well turn them into single band 75 meter amps and disconnect all the other bands. As the op frequency goes up, trouble starts.

BTW I stripped #2 down to the last screw and I'm going to build it back up. I'm not giving up on none of it. I can buy 10 Gonsets for the price of 1 SB 220. If I can figure out what's wrong, I'll be way ahead. I was listening to some slop bucket on 75 last night talking about how his ICOM PRO 756 that he paid 4500 bucks for had be sent back to ICOM. It kinda reminded me why I like doing what we do. 4500 bucks?

for now, get the Matchbox done and out of the way so I can get on again. I'm gonna check the coil supports right now. Maybe the stuff took this time. I papered it with 120 grit.

and thanks for your help, OM.

[The Slab Bacon]

Timmy, FWIW, I think the problem is that the filament choke and plate choke are insufficient for the job at hand. Especially that little wimpy-assed filament choke.
And, er, furthermore, the HV lead from the bottom of the plate choke lays right next to the wimpy little plate choke, creating an easy feedback path. That is why I added a .01 / 3kv bypass cap at the bottom of the plate choke. I figgered that it couldnt hurt. One major design problem is that there is really no room for a bigger filament choke. So I also added some additional bypass caps at the transformer end of the fil choke. Hopefully this should stabilize things a little better.

                                                                      The Slab Bacon

[N3DRB The Derb]

I agree with your assessment of the plate choke, it's a joke. A National 152 or 175 in there  or a pie wound BUD would be much much better. I'll be looking for just that at the fester. Another thing, a few VHF rated ferrite beads on the filament choke leads might help things.

I'll parallel whatever you've done with #1 with #2 when I get back around to working on it after the DRB Box is buttoned up and done. It looks like the coil support held this time but I didnt really crank on it. just going to slap the coil on it, connect the taps and connecting straps
and tune up. Yeasu #1 is kicking ass and ready.

[N3DRB The Derb]

It didnt hold.    see BOING thread for disgusting roadkill pix.