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The spec's say that the Eventek switcher has "ripple and noise" of "0.5% V P-P", so 0.005*12 = 60mv P-P at 12v out. The MFJ4230MV has "ripple and noise < 100mv", that may be rms, definitely worse than

I am currently in the same situation. I have a simple lapel mic and every time I plug it in the rig goes into transmit mode, it's almost like there's a short. I've attached the diagram from the BitX40

If using plastic boxes or the like, you can line the case and shield in important areas with copper foil available quite cheap on ebay:

I hope that fine case maker in India comes up with a slope front case for the JackAl add-on with options for 5" or 7" display.? I currently have a plastic case uBitx and it works fine. -- Lee -

Well when we build a radio into a metal box, then attach several wires to it, that can compromise the shielding. And cut a large opening for a display its not as shielded. I have a slight preference

The Tekpower TP3005T looks like an excellent bench supply. A linear power supply using a tapped transformer, so likely cleaner than most switchers, still reasonably efficient. Though at $80, kind of

Hi, Shielding also protects the receiver circuits from external "crud". So much for the QRP argument. *All of my radios live in steel or aluminum, even the one with pretty plastic panels on the

STREAM of solar wind is approaching Earth and experts fear it could hit us as early as November 26 [email protected]> wrote:

If you don't care, a metal case is probably best so you can shield it. I'm doing one for my personal use that has a metal surround, but plastic end panels (easier to cut). However, the "display model"

This was my scope capture with the CW key pressed. ? John, K5GT

Barry, Evan, Thanks... It is good to know that microphonics an happen to a working board.? Now I can chase other things that may be part of the distorted audio and low sensitivity!? ...Then on to

On Sat, Nov 24, 2018, 11:09 Lee <mr.olson@...> wrote: > Some have built in metal boxes, some use plastic boxes, and some put metal > shielding inside the plastic boxes. Is it a ,should do,

Hi all, So far hadn't touched my uBitX v3 for a while. This week I started building the AGC-kit I had ordered a while ago and added another 3.5mm audio connector to make a separate connection for a

Some have built in metal boxes, some use plastic boxes, and some put metal shielding inside the plastic boxes.? Is it a ,should do, must do, or doesn't really matter at these low power levels.??

Looking at the output of my uBITX on 160m on a spectrum analyser, you don't want to go there! However, a simple external low pass filter makes all the difference. Attached is the circuit of a LPF that

Supplies made for amateur radio are usually quiet. You don't need instruments - if you hear the supply in your transceiver it's too noisy. I have two 30 amp linear supplies, but my precocious desktop

Looking on the components side of the Bitx 40 board right side about 1/2 way, I see a 2 prong connector labeled TUNING. My instruction sheet from HF Signals shows nothing, no connections. anyone have

If you bought one and decided not to use it, I'd like to fine one.? ? Thanks John K5MO

my rad had a bad usb port on it. turns out i had to nudge a small tang of metal inside the connector on the nano. if your cable goes vall the way in the disregard this post. Dave n4lkn

Unfortunately, that battery is only rated for?235 mAh.? On a BITX40, it would have a short, but happy, life.