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Bitx40v3.5 exciter plus Qrp PA -prototype-

 

Hi colleagues
Here my version of the Bitx40v3 TH(throug hole)
I have tested the Qrp PA and it works excellent after fried two LPF 470 pF ($0.01) capacitor, one by one.
Now I want to test both together
I hope to get the same performance as other I have made.
Qrv's?
73's Jc

Bitx40v3.5 PCB plus PA.png
Bitx40v3.5 PCB.png

 

Doyou have a sprint layout file ?
Timothy Fidler
 

You need to be using dogbone Silver mica capacitors or you might get away with? 600 V ceramic capacitors.? You can't use standard ceramics at 50 or 100V rating on this duty.? ?Diz at Kits and parts / Toroid king sells Silver mica capacitors from the US.? Other than that they can be hard to find.? There are also specialised tongue in metal tube SM capacitors for transmitting power but they are also very expensive and not for self constructor use unless you have large amounts of spare cash.?
 

Dear JuanCarlos,

pl share the schematic too related to these boards.

73 de Rajendran.VU2SMM
 

PCB board PDFs would be fine for those who want to make their own pcbs apart from the circuits
Regards
Lawrence

On Wed, Jan 23, 2019 at 3:49 PM Rajendran Mayilsamy <mrajsuba@...> wrote:
Dear JuanCarlos,

pl share the schematic too related to these boards.

73 de Rajendran.VU2SMM
 

The silver $2 each mica parts are something many of us hams learned to use 50 years ago.
Today's $0.02 C0G/NP0 surface mount ceramic caps in a large package (at least 1206)
from a quality manufacturer should work about as well in this application.?
Avoid dielectrics other than C0G and NP0, make sure you have a sufficiently
high voltage rating of maybe 200 or 500 volts.? ?And I would not buy them on ebay.

There's a reason that silver mica dogbones are getting hard to find.

Jerry


On Wed, Jan 23, 2019 at 12:02 AM, Timothy Fidler wrote:
You need to be using dogbone Silver mica capacitors or you might get away with? 600 V ceramic capacitors.? You can't use standard ceramics at 50 or 100V rating on this duty.? ?Diz at Kits and parts / Toroid king sells Silver mica capacitors from the US.? Other than that they can be hard to find.? There are also specialised tongue in metal tube SM capacitors for transmitting power but they are also very expensive and not for self constructor use unless you have large amounts of spare cash.?

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