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Good news...I did NOT blow up my uBitX #ubitx #ubitx-help

Gwen Patton
 

I thought I blew out the PA 12v trace trying to tune it on 160m, but I guess I didn't. I think the 12v power connection was slightly intermittent on the board, possibly from a slightly loose connection in the 3-pin socket. The clue was that it was drawing NO power at all when turned on. If I blew the PA line, the Raduino probably should have turned on, and I think I should have drawn SOME power. So there was the possibility I blew the Raduino...but then the PA section should have drawn some power, shouldn't it? So I checked to see if I was getting 12v on the red wire to the 12v connector on the board. Didn't get it at first...then pushed down on the metal connector inside the plastic plug body with my voltmeter probe, and suddenly it started working again! The Raduino powered up and I started getting sound. Woo hoo!

I buttoned it up and it kept working (though there's something not quite right in the BNC connector, need to open it back up and check that), so I put an antenna on it and started noodling about for signals. I compared it to my KX3 and the K3FEF SDR, and I see that a signal on 14.045 on K3FEF zero beats to 14.045.74 on the uBitX. I'm assuming I need to recalibrate it? Or am I mistaken?

I looked in the "tune up" section in the docs. Is this the zero-beating to an AM broadcast station part? When it talks about the actual carrier frequency, if I'm tuning it to a station on 1060AM, would that be the carrier frequency, or is there some magic offset I'd need to calculate (hopefully no integration...I never took calculus)?

I'm very glad to have this radio functioning again, but I can't take it into the field with the tuning so far out. I'd appreciate some advice.

73
Gwen, NG3P

Dexter N Muir
 

Hi Gwen and all:
Something about Americanisms (NZ English IS English, not quite so severely mangled):

"started noodling about for signals": I take it "noodling" is investigating, i.e. using one's head - one's NODDLE - the bit of you that nods? I hadn't encountered 'noodling' until SolderSmoke, and it jarred. After all, I don't think we have noodles atop our shoulders. :) Still, I suppose noodles are sort of descriptively squirmy-wormy ...

73
Dex ZL2DEX

Curt
 

Gwen

Nice to cross paths again. Be patient while you figure this rig out.

The frequency display represents the missing carrier frequency on ssb. The frequency where transmit happens on cw will be about 700 Hz. This is because the ubitx doesn't have a cw mode, but it switches to the cw path. We just learn to add or substract 700 Hz depending upon usb or lsb. Now the ssb frequency is often a little off when delivered. So tune into a known ssb or am signal to check it out.

Curt

Jerry Gaffke
 

The BNC socket included with the kit is not machined to tight enough tolerances,
the hole to receive the pin is cut too large in some cases,
and the center conductor is an open circuit. 

This is not an issue of 50 vs 75 ohm connectors.
The connector is built as a 50 ohm BNC socket,
and is mechanically compatible with the 75 ohm flavors.
At HF, would not matter if you did substitute a 75 ohm connector.

Best bet is to buy a new BNC connector.
Or maybe steal an RCA phono connector off of an old stereo.

Jerry, KE7ER



On Tue, Sep 10, 2019 at 12:50 PM, Gwen Patton wrote:

there's something not quite right in the BNC connector

Jim Willis
 

I had this problem and went with a SO-239.

 

73 de KX4TD

 

From: BITX20@groups.io <BITX20@groups.io> On Behalf Of Jerry Gaffke via Groups.Io
Sent: Tuesday, September 10, 2019 8:11 PM
To: BITX20@groups.io
Subject: Re: [BITX20] Good news...I did NOT blow up my uBitX #ubitx #ubitx-help

 

The BNC socket included with the kit is not machined to tight enough tolerances,
the hole to receive the pin is cut too large in some cases,
and the center conductor is an open circuit. 

This is not an issue of 50 vs 75 ohm connectors.
The connector is built as a 50 ohm BNC socket,
and is mechanically compatible with the 75 ohm flavors.
At HF, would not matter if you did substitute a 75 ohm connector.

Best bet is to buy a new BNC connector.
Or maybe steal an RCA phono connector off of an old stereo.

Jerry, KE7ER



On Tue, Sep 10, 2019 at 12:50 PM, Gwen Patton wrote:

there's something not quite right in the BNC connector

_Dave_ K0MBT
 

Hi Gwen
It is lucky to survive there is no filter section for 160.

I wouldn't zero beat to a broadcast band signal it is too low to be really accurate at higher frequency. Zero beat it on some higher frequency AM station in the short wave region. 

Should work fine just stay off the band edges eh!

Perhaps you can align it to your kx3 if that suits you for quality of frequency alignment.
Tx into a dummy load.

Have you fit a Nextion display and wb8cec firmware. They bring some things out that it can't really do well without it. 
--
73
Dave
k0mbt
Ham_Made_Keys

Gwen Patton
 

No touch screen mods yet. Maybe now that I know I didn't fry it!

Yes, noodling is slang for wandering about or randomly experimenting. I should be more conscious of slang I such an international mailing list. You never know what's going to be a mortal insult in another culture!

Thanks for the suggestions, everyone. I'll probably going to install an SO-239.

73,
Gwen NG3P

Ralph Mowery
 

In the south of the US noodling is where you go to a river, get in the water and reaching holes under the water and try to find catfish and pull them out by hand, in addition to slang about searching for something.

To calibrate the BITIX tune to 5, 10 , or 15 MHz and find the time signal WWV.  The carrier will be exactly on one of those frequencies.  The higher one the better.  There is also one at 20 and maybe 25 MHz. If you don't know about it, it will sound like a ticking clock and every Minuit will give the time.


On Wed, Sep 11, 2019 at 6:53 AM Gwen Patton <ardrhi@...> wrote:
No touch screen mods yet. Maybe now that I know I didn't fry it!

Yes, noodling is slang for wandering about or randomly experimenting. I should be more conscious of slang I such an international mailing list. You never know what's going to be a mortal insult in another culture!

Thanks for the suggestions, everyone. I'll probably going to install an SO-239.

73,
Gwen NG3P
_.__,_

Gwen Patton
 

Ok, I've replaced the BNC with an SO-239, and that is working a lot better. CW, though, is a problem. I had originally wired it for straight key, but decided to try wiring it for paddles instead. I added the 2.2k and 10k resistors, put them in the line as shown in the schematic, and connected them to the key socket. (I use W0EB's little breakout boards for this. Much easier to get at the thing.) Problem is, I STILL don't have paddle functionality. It's only operating in straight key mode.

I looked through everything, ran through the menus, and didn't find a place to change the hand key/paddle mode -- I gather that's in a different firmware set -- but I thought that it would work automatically once the voltage divider was in place. It's still only working with the sleeve connection for dah. I need to open it BACK up and start chasing things with the ol' multimeter, but if anyone can think of something specific to check, I'd appreciate it.

This is a v3 board, no mods. I hadn't gotten around to modifying anything since I thought I'd blown it up. If I MUST, I can operate it with a straight key, and maybe even a Cootie, but it seems very squirrelly with a Cootie -- noisy, lousy contact, that sort of thing, even right after cleaning the contacts. I hit them with Deoxit regularly and pull a piece of paper through the contacts to take off any corrosion or tarnish.

73,
Gwen, NG3P
Who has to stop fiddling with gear and practice CW more...L2 class on Monday!

Curt
 

Gwen

Look again, I remember a menu setting in the stock firmware to designate using a paddle. I remember a few have fiddled some with those resistor values. Perhaps also check the entire path resistance,  after finding the setting.

Curt

Gwen Patton
 

I finally found it. What threw me was that you have to turn on Setup mode, then dial PAST "Exit Menu" to find the select for the key type. Got it working! Thanks, Curt!

73,
Gwen, NG3P