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73

Today I was greatly and pleasantly surprised.? I'd mentioned that I was thinking about converting my BITX20 to 40 meters, and I'd related some stories of frustration with the local ham community (generosity and willingness to help others seems to be a rarity in this area).

When I got our mail, there was a package in it - with a BITX40!? The housing it was in is very attractive as far as my wife and I are concerned - and perfect for our car.? The neat part was that you could see the circuitry in it - and the case also would lend itself to portable operation!

I won't embarrass the sender, but I will say it came from another state.? For many years, I've insisted that there was no such thing as Karma... but this suggests otherwise!

To the sender (not named) - a big Thank you! from both of us, and (laugh) no worry about "paying forward" - we do things all the time like that, whenever we can (we may not have much money, but we do have skills and knowledge we share).? Generosity and helping others is not a big price for gifts like this - in our opinion!

The only cb ones I have tried on 2 m are the long parallel rod pick up type, they were quite in accurate

For VHF/UHF I use ham products made for the purpose

Cheers

Gordon kx4z

On Sep 9, 2018, at 13:59, Bill Cromwell <wrcromwell@...> wrote:

Hi,

It might start to be a little shaky on the two meter band. And maybe will work there too.

73,

Bill KU8H

On 09/09/2018 05:37 AM, gonewiththeego@... wrote:
I was thinking about an Albrecht SWR 20 which I can see that is used
only for CB. Do you think it should work for 20/40m band ?

--
bark less - wag more

On Sep 8, 2018, at 3:01 PM, Mark Rosenthal <marksro@...> wrote:

I searched for this problem to no avail. So I am posting in case someone has an answer.
I bought a new uBitX, and installed it in the case from Amateurradiokits.in.
Upon powering up the display shows:
uBITX v4.3
LSB A: 7.149.950

If I turn the encoder to change frequency, the display shifts from 7.149.950 to 7.149.900. back and forth as I turn, either CW or CCW.
If I push the encoder, the display shows Band Select >
Turning the encoder does nothing
Push encoder again and I get display showing Band Select:
Turning the encoder now changes display between 7.349.900 and 7.149.900.

If I power off, then back on, sometimes the frequencies shown in the display are a little bit different (some times when in band select, the display will change from 7.149.900 to 6.949.900, or similar).

With an antenna attached I can hear signals from the speaker (noise, occasionally someone’s transmission). So I know the receiver works. If I push the PTT the relays click. I assume transmitter works too.

I thought I had a bad encoder, so I bought a new one from Digikey. Same results.

Power supply is 13.27 volts.
Power to raduino is 5 volts.
Someone suggested pin 3 may be shorted to ground causing raduino problems, but I checked and not grounded.
All wiring triple checked (or more).

Any thoughts are appreciated.

Thanks
73
Mark
W3MSR

Thank you very much for your nice "Welcome aboard", indeed I appreciate all
of the answers above and I'm pretty sure that this topic will have some
"echo" throughout community. These are maybe the most common questions asked
by those with just the license of operation in hand and a few basic
knowledge of electronics. I can't wait to see the uBitx on my desk.
Meanwhile, I can't find some genuine information about the output impedance
of the uBitx itself. Is it 50 ohms ? Gordon Gibby previously sugested that a
CB SWR-Meter will do the job on HF also. I found one but it's rated to 11m
band only, or at least that's what on the label. Can someone tell me what
can go wrong it I start using it ? And by experiment, does anyone know how
much SWR can uBitx handle without permanent damage?

It looks like great progress is being made on spur reduction, so back to LPF switching and a few other things. Received the first set of boards and have already made some modifications for better wireability.

1) I decided to eliminate R3 off the uBITX board and instead add it to the LPF Relay Board because it frees up space on the uBITX and allows more efficient RF wiring for receive. Since the "old R3" also switches M1 to M2, I'm changing that to how it's wired on the V4 uBITX by adding a 2N7000, changing R70 to 1K, add a 1K R78, add a 1uF C79, add a D14, and driving the 2N7000 with a line over to T/R (a 2N7000 driven directly by T/R is faster than any speeding relay contact).

2) Replace 3 sets of dual 2N3904 Transistors in the PA driver with 3 sets of dual 2N2222A Transistors. Allison had suggested changing the emitter resistors from 22 ohms to 10 ohms (for dual 2N2222A's ??

3) Add a three 1N4148 diode-OR from TxA,TxB, and TxC driver inputs to a TxD driver to pick that relay, which removes the 10m/12m/(15m) LPF when inserting the proper (A/B/C) LPF during Tx. Yes, that means 4 relays are active during TxA,TxB, or TxC transmit. All four of the LPFs use the existing inductor/capacitor components off the uBITX board. They are just moved over to a small 1.5" x 0.5" bare LPF board (that footprint is also the one QRP labs has for their LPF/BPF filters, but they don't sell blank boards.

4) uBITX Antenna will be wired to either one of two SMA connector pads.

5) T11 will be connected to the RF input on the LPF Relay Board with about 1" of coax.

8) Will provide pictures later.

73 Kees K5BCQ?

_._,_

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<PCB_LPFx4_.pdf>

<PCB_LPFx4_bottom.pdf>

Output of the uBITX is 50 ohms.? Your CB SWR meter should work for the upper end of?

HF range (20M through 10M) and maybe acceptably good for 80M through 10M.? Many?

of those old CB SWR meters were just copies of ham radio SWR meters of the era.??

If the CB SWR meter is not performing well, it does provide a case, meter, and knob to?

use in building a more modern bridge type SWR and power meter.

Arv

_._

On Sun, Sep 9, 2018 at 1:12 AM, <gonewiththeego@...> wrote:

Thank you very much for your nice "Welcome aboard", indeed I appreciate all of the answers above and I'm pretty sure that this topic will have some "echo" throughout community. These are maybe the most common questions asked by those with just the license of operation in hand and a few basic knowledge of electronics. I can't wait to see the uBitx on my desk. Meanwhile, I can't find some genuine information about the output impedance of the uBitx itself. Is it 50 ohms ? Gordon Gibby previously sugested that a CB SWR-Meter will do the job on HF also. I found one but it's rated to 11m band only, or at least that's what on the label. Can someone tell me what can go wrong it I start using it ? And by experiment, does anyone know how much SWR can uBitx handle without permanent damage?