[Amps] 10 KW CCS ON 6M...USING THE 3CX-6000A7... PART 16

[John Lyles]

Jim, you could subtract your meter lead resistance from each winding 
measurement, its even better. Also, notice that the value of R slowly 
dropped. This is because the secondary is resisting the step change flow 
of current, just like a capacitor resists a change in voltage. Be 
careful about having hand on each probe as there might be kick, the EMF 
from disconnecting that continuous current. It used to be much worse 
when using a Simpson 260 VOM. Don't ask me how I would know that.

That is an awfully heavy iron part to place on a sheet metal chassis 
bottom. It might help to add some flat stock across from end to end, 
like 2 inch wide aluminum bars. This spreads the load and prevents 
dimpling of the sheet metal. In commercial transmitters with even 
smaller transformers, we used 3/8 steel plate for the bottom and drilled 
holes, welded nuts on the bottom for bolting the iron in. This also had 
some I beams welded to it, so that a pallet jack or fork lift could move 
it. That would be overkill for yours.

73

John

K5PRO

> Message: 1
> Date: Tue, 21 Feb 2023 12:53:20 -0800
> From: "jim.thom jim.thom at telus.net" <jim.thom at telus.net>
> To: amps at contesting.com
> Subject: [Amps] 10 KW CCS ON 6M...USING THE 3CX-6000A7... PART 16
>
> Here, finally the 17.6  kva CCS / 280 lb custom Heyboer plate xfmr is
> unpacked.
> B+ supply is being built this week.  I specd' the pri + sec taps, temp rise
> over ambient, max secondary DC resistance etc, for Scott.  Scott just moved
> into a bigger home...on 2 acres, on Feb 10th, so he was tied up with the
> huge moving endeavor, removing old tower, and packing hundreds of lbs of
> radio gear to the new workshop. .
>
> https://www.youtube.com/watch?v=og9hwdIaIXk