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Re: CAT Control

 

The Nano clone that comes mounted to the stock Raduino board
that comes with the uBitx and Bitx40 from hfsignals has a CH340 chip.

All the $3 Nano clones that folks buy to replace a fried Nano have the CH340 chip.

The original Nano board used an FTDI chip, not the CH340 chip,?
but nobody here coughs up the $20 for that board.

Your FTDI cable should have worked, if connected properly to D0 and D1 for the UART connection.
Must connect the cable's RXD to the Nano's TXD (D0), and the cable's TXD to the Nano's RXD (D1).?
Must also have a ground connection from the cable, and some way to power up the Nano (radio turned on is sufficient).

Under Windows, you need to install a CH340 driver to use the clone Nano's.
Under Linux, the needed CH340 driver is usually already there.
Under Mac OS-X, some drivers don't work, there are forum posts about this.
On a? Rasberry Pi, it can be done, my guess is the driver is already there for the typical Linux os install.

Jerry



On Fri, Jun 8, 2018 at 01:36 am, Tom, wb6b wrote:
Hi Dennis,

See this post.?/g/BITX20/message/51600

Hope this helps.
Re: K5BCQ kits in BITX40 #bitx40

 

I update the list every 1-2 days. You can check the status of kits being ordered and shipped at the link below. Sometimes i make several trips to the Post Office if I happen to be going that way.

73 Kees K5BCQ

Check here...
/g/BITX20/files/K5BCQ/K5BCQ%20AGC-Audio%20Kit%20OrdersALPH.ods


?
Re: Spurs for Dummies? #ubitx-help

 

I'll keep my summary very short: do all the mods you like but make a high pass filter to cut the frequencies below 28mhz. Adding a tuner will also help. That's all folks.


Il 08/giu/2018 16:19, <davedt1e@...> ha scritto:
I've been following the discussion on spurs, but not sure exactly what it all means in practical terms.? I'm still a tech so 10 meters is of some importance to me.? So far, it's my understanding that this effects the bands above 20 meters when mic gain mods are added. Is that correct? Specifically I'd like to know what mods I should stay away from.? I was planning to add one of the simple mods involving just a few resistors to increase mic gain.? I'd also like to do one of the simple mods to bring my 10 meter output up to 4 watts or so.? Can I still make these changes and stay in compliance.

It would be very much appreciated If someone could give a short summary of the Spurs issue for us less technical folks.

Thanks!

David

Re: IFshift

 

This may be dumb but could you use varactor ?diodes in the filter circuit and vary the voltage to them to change the capacity in the circuit to vary the band width. The Electraft K1 uses this type of adjustable filter ?routine. Years ago I copied ?it and used it in a TenTec ?1340 kit and it worked pretty good.?
73's ?kn4ud ?
--
Allen ?Merrell
Re: RF power chain mods and improvements..

 

As a complete re-design of the RF low level chain I was thinking of trying BiDiAmps based on MMIC (BGA2851 seems a a good candidate as its price is low) and use BFU550AR for Q90 and 2N2222A for predriver and driver stage. Keep the IRF510 as finals.
Add a common gate, switched when needed, JFet preamp for higher bands.
I have some BGA2851 on order and I would try that first, see how it works. They are requiring 5V supply and only take about 7 mA, so the receiving power draw will also improve.
Any thoughts, reccommandations ?

--
Ion

VA3NOI
Re: Noob Mic question #ubitx-help

 

How do you like the giant fan?? If I turn it on I half expect the radio to go sliding across my desk.? It's gotta go. Lol.
Re: RF power chain mods and improvements..

 

It would be nice would be to have a level 3-5 watts across all bands, 80-10. I was thinking of building an amplifier based on the old Motorola EB-63 application note. The amp would use real RF transistors instead of the IRF530 types coming out of China. Those amps have the same problem as the uBitx with power dropping as frequency increases. The problem with using the uBitx to drive an external amp is the output variation across frequency. There is no easy way to solve that problem.

Allison, if you can get the uBitx to produce 10 - 8.5 watts from 80 to 10, that would also work. It appears you are getting close to that goal. That would allow the uBitx to run barefoot with a decent output power on all bands. Driving an external amplifier could be accomplished with a simple attenuator pad. Additional bandpass filtering would probably be required between the uBitx and amp input.

Ray
AB7HE
Re: Noob Mic question #ubitx-help

 

Looks nice.? Great idea of re-purposing an old lamp.
--
Lee - N9LO? "I Void Warranties"

?
Spurs for Dummies? #ubitx-help

 

I've been following the discussion on spurs, but not sure exactly what it all means in practical terms.? I'm still a tech so 10 meters is of some importance to me.? So far, it's my understanding that this effects the bands above 20 meters when mic gain mods are added. Is that correct? Specifically I'd like to know what mods I should stay away from.? I was planning to add one of the simple mods involving just a few resistors to increase mic gain.? I'd also like to do one of the simple mods to bring my 10 meter output up to 4 watts or so.? Can I still make these changes and stay in compliance.

It would be very much appreciated If someone could give a short summary of the Spurs issue for us less technical folks.

Thanks!

David
Re: Building homebrew ubitx: Need pre-v3 schematic PDF. Also, source for 45M15 (45 MHz IF) filter?

 

Thanks? Vince for clarification on local shipping charges.

Regards
MVS Sarma
?

On Fri, Jun 8, 2018 at 7:13 PM, Vince Vielhaber <vev@...> wrote:
Within the US, a First Class package up to at least 3 oz is $2.66 (it may be more than 3 oz, I don't have anything 4-9 oz and 10 oz is more than 2.66).? First Class is good to a pound.? Priority Mail starts around $7.20 for flat rate.

Vince.


On 06/08/2018 12:51 AM, Mvs Sarma wrote:
Ifear the minimum shipping charges even within US using postal service
is $6. That is what kits and parts charge their customers within us.

Regards
MVS Sarma


On Fri, Jun 8, 2018 at 9:20 AM, Ashhar Farhan <farhanbox@...
<mailto:farhanbox@...>> wrote:

? ? It is just that shipping takes 10 dollars from india for a two
? ? dollar device. Someone in the USA cam undertake thr shipping. I can
? ? send a bunch? to someone from here.
? ? - f

? ? On Thu, 7 Jun 2018, 17:50 David Feldman via Groups.Io,
? ? <wb0gaz=[email protected] <mailto:[email protected]>> wrote:

? ? ? ? 49.152 MHz crystals can be obtained in fundamental mode (mostly
? ? ? ? in SMD package; 5x7mm is not too difficult to work with, but
? ? ? ? smaller packages certainly are), however, check datasheets
? ? ? ? carefully and confirm with manufacturer if in doubt, as many
? ? ? ? also are offered in 3rd overtone or don't specify. Above 49.152
? ? ? ? MHz, fundamental mode crystal seem to be rare.

? ? ? ? That said, I believe the project should consider making the 45
? ? ? ? MHz filter normally used in the project available for sale to
? ? ? ? homebrewers as a component or spare part (perhaps in quantity
? ? ? ? increments of 1, 10, 25, or something like that); this would
? ? ? ? greatly help those that want to duplicate or otherwise follow
? ? ? ? the commercial design and help support volume purchases by the
? ? ? ? project from OEM in China, and would help homebrewers focus on
? ? ? ? individually interesting parts of the design without having to
? ? ? ? resort to making individual design changes in that part of the
? ? ? ? circuit.

? ? ? ? Thank you,

? ? ? ? Dave






--
? Michigan VHF Corp.? ?? ?
? ? ? ? ? ? ? ? ? ? ? ? ?




Re: Noob Mic question #ubitx-help

 

Here's that pic I promised.? Made from an old desk lamp from a resell it shop.? Not much to look at,...but it serves my purpose.? Used some vacuum tubing to attach the mic element and hot glued a handfull of nuts into the base to give it some weight.
Re: Building homebrew ubitx: Need pre-v3 schematic PDF. Also, source for 45M15 (45 MHz IF) filter?

Vince Vielhaber
 

Within the US, a First Class package up to at least 3 oz is $2.66 (it may be more than 3 oz, I don't have anything 4-9 oz and 10 oz is more than 2.66). First Class is good to a pound. Priority Mail starts around $7.20 for flat rate.

Vince.

On 06/08/2018 12:51 AM, Mvs Sarma wrote:
Ifear the minimum shipping charges even within US using postal service
is $6. That is what kits and parts charge their customers within us.

Regards
MVS Sarma


On Fri, Jun 8, 2018 at 9:20 AM, Ashhar Farhan <farhanbox@...
<mailto:farhanbox@...>> wrote:

It is just that shipping takes 10 dollars from india for a two
dollar device. Someone in the USA cam undertake thr shipping. I can
send a bunch to someone from here.
- f

On Thu, 7 Jun 2018, 17:50 David Feldman via Groups.Io,
<wb0gaz@... <mailto:[email protected]>> wrote:

49.152 MHz crystals can be obtained in fundamental mode (mostly
in SMD package; 5x7mm is not too difficult to work with, but
smaller packages certainly are), however, check datasheets
carefully and confirm with manufacturer if in doubt, as many
also are offered in 3rd overtone or don't specify. Above 49.152
MHz, fundamental mode crystal seem to be rare.

That said, I believe the project should consider making the 45
MHz filter normally used in the project available for sale to
homebrewers as a component or spare part (perhaps in quantity
increments of 1, 10, 25, or something like that); this would
greatly help those that want to duplicate or otherwise follow
the commercial design and help support volume purchases by the
project from OEM in China, and would help homebrewers focus on
individually interesting parts of the design without having to
resort to making individual design changes in that part of the
circuit.

Thank you,

Dave




--
Michigan VHF Corp.

Re: K5BCQ kits in BITX40 #bitx40

 

I have informed delivery Doug, today a package from China is arriving and Monday a package from Colorado.
So maybe the package from Kees is coming from Colorado but saw his location is in TX.?

John
Re: uBitx Encoder information needed.

Bo Barry
 

Jon! ?A pleasure seeing your name. My short term memory is shot, ?but I remember the 70's well! And enjoyed your books!
Unfortunately I didn't go the 8008 way, a friend gave me a 6800 set and I went the SWTP way, one board a payday.

I see you picked an ideal retirement location! My daughter is in SLC and I wish I could live there.

Your many accomplishments don't match up with your college accomplishments tho.

Sorry for the 'off topic', ?but Jonathan has contributed so much to my enjoyment!
73, Bo W4GHV since '54
Re: CW transmit bandwidth #ubitxcw #ubitx

 

How did you measure the bandwidth?

Remember that a square wave is a infinite series of odd harmonics. Your
keying is basically a square wave unless modified to have a rounded
up-slope and down-slope. Even then you will still have some odd
harmonics that cause the bandwidth of a repeating on-off dot or dash to
have a bandwidth increase over just the carrier itself.

tim ab0wr


On Thu, 07 Jun 2018 12:37:33 -0700
"K3OS" <garysch69@...> wrote:

Just got a v3 board running today.? I was monitoring CW on my IC7300
and noticed that when transmitting, i.e., a string of dots or dashes,
the bandwidth would widen to 1Khz then return to very narrow.? ?This
occurred at a periodic rate if I held the dot or dash lever.
Internal keyer was used.? When sending text the same issue occurred
but it was more difficult to spot.? Initial test was 40 meters, 12
watts out, but same results on 20, 8 watts out all into a dummy.
12.2VDC power supply.?

Any clues to why this happens and what can be done?

Gary K3OS
Re: Power supply fuses

 

¿ªÔÆÌåÓý

I used asmall fuse with pig-tails (All Electronics) and put it at the input power connector like you show.

You show outside ring of connector +.

I usually make the center pin of the power connector +, but many wall warts differ?

ALL Electronics has the fuses cheap, 3 or 4 Amp.? They have some nice 12V supplies with 2.1mm DC connectors too.


Mike, WA6ISP



On 6/7/2018 10:58 PM, Mvs Sarma wrote:
The corrected diagram is here. 

-- 
Mike Hagen, WA6ISP
10917 Bryant Street
Yucaipa, Ca. 92399
(909) 918-0058
PayPal ID  "MotDog@..."
Mike@...
Re: Power supply fuses

 

I do the same except I just tape mine to the back panel with masking
tape. Lot's easier to remove than cutting a tie wrap.

tim ab0wr

On Thu, 7 Jun 2018 13:12:24 -0700
"Michael Hagen" <motdog@...> wrote:

Yes it should work fine,? might knock down the power a little. Would
be better with 4 Schotky diodes.

They are going to HEAT!?? Probably over a watt for each of the 2
conducting diodes.? On battery it would be quite a waste of power.

Another detail,? chassis radio ground and 12V - battery input are not
common. but separated by a diode?

I put an extra fuse inside the cabinet and just a 1N4007 to ground.
Ty wrapped extra fuse to some wiring.? I have never blow it.


73's

Mike
Re: CAT Control

 

Hi Dennis,

See this post.?/g/BITX20/message/51600

Hope this helps.

Tom, wb6b
Re: CAT Control

 

Hi Ashhar,

Doesn't work yet. Pulled FTDI cable and replaced it with the usb cable connected to the Arduino nano. Set up wsjt-x as instructed - baud rate at 38,400.Test button fails for every combination possible.

Went to device manager for usb Serial and it says the drivers for this device not installed. I have it search automatically for the driver, but it can't find one. Not sure if this is the problem or not. I am using a usb sound card for audio in and out - that seems to work fine. The USB connection should be ok as I used it to upload the updated sketch.

73, Dennis
W7DRW
Re: K5BCQ kits in BITX40 #bitx40

William Londree
 

I was a last minute order and was very surprised to receive mine this morning. Very nice professional looking kits. Did not take long at all in my case. Within a couple weeks! I paid by check.

Bill W6SDI
Ventura, CA
65341 - 65360 of 116681