Hi All, I'm new to the uBitX v6 and I have been scouring the group for the essential mods. I have a strong AM broadcast station close to my QTH, so a broadcast band filter is a necessary mod before I can use the radio.? As far as I can tell the top changes are:

• New firmware: It looks like the N8ME software is the winner for the v6.? The stock firmware looks very barebones.??
• Broadcast band filter: Because of my QTH
• AGC: Lots of options here.? Any guidance is appreciated.

Anything else or other opinions?
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73, Greg, KM5GT

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I’m also new to the v6 and can’t provide much guidance. ?My grandson got one a month ago and installed the Nextion display and the CEC firmware. ?He made a few contacts and then the radio stopped working. ?He is getting ready for grad school in Denver this fall so hasn’t been able to spend any time with it for the last couple of weeks. ?So I decided that I should try one nd was impressed with the fast delivery.

I would suggest a look at the N8ME with the VU2GAO mods available in the files section of this list.? That fixes most of the issues, and as long as you are OK with the more straightforward graphic interface and do not need an S-Meter, it is a good choice.? The software is free and works on the stock hardware.

For a BCI filter, I use this one:


It has worked well for me.

For the last v6 I modified for a ham friend, I used a design based on a light-sensitive resistor and LED.? I worked well as far as I know, as I have not heard of any complaints from the other ham.? I attached the document that describes what needs to be done.? The tricky part is to find an LDR that is low enough when fully lit to reduce the volume.? I bought several different packs and tried them.? I found that you need a dark value of around 50k-100kOhms and a full bright value of 1kOhms.


Attached is a PDF with the base documentation that I used.? There is not a kit available that I have found.? The one I used prior was in the RF line and worked well, with the advantage that you could add a 1kOhm variable resistor to attenuate strong signals for better selectivity.? I read that it is good practice for contests and DX hunting.

Links demonstrating the circuit:



Some notes on the AGC:
1 - you will need an LDR that can go down to 1kOhms when fully lit
2 - 2n2222 or 2n3904 transistors work
3 - Take the input from TP20, and the LDR is across the volume control
4 - I would put the variable resistor on the front panel so that you can adjust the amount of reduction.

I hope the above helps.
73
Evan
AC9TU

Hi Greg
I have modified several V6s and I agree with Evan about the firmware. ?I use the little BCI kit from qrpme.com, either internally by cutting a trace (my mod for that can be found on ubitx.net) or externally in the coax line. ?Both work well.

If you are interested in CW, one of my blog entires covers the things I did to make mine "CW Worthy" and there is also an entry about making a AVC using an LED.


Have fun with this.

73 Howard K4LXY

Thanks all.? I appreciate the pointers here, and the PMs I received as well.??

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73, Greg, KM5GT

Hi Evan,

I want to thank you for the info on the N8ME/VU2GAO mods software, I've been so wrapped up in the sBitx project that my V6 has been collecting dust on the shelf running Reeds software. I'm really impressed at how well the N8ME/VU2GAO mods software works, it's kind of like getting a new radio.

Joel
N6ALT

I'm afraid I have to retract what i said about the N8ME/VU2GAO software, after using it for a little while I realized the BFO was off a little bit and that's where it all went down hill fast. I went into the calibration screen and adjusted the BFO, then I found the VFO was way off frequency so I adjusted that also and exited the calibration screen, I then tried to check into a net, when I un-keyed the VFO was way high in frequency so adjusted it again but the number kept changing every time i did it until it was so far out that it no longer received. I reloaded the N8ME/VU2GAO software onto a new Nano and started down the rabbit hole all over again. After hours trying to get it calibrated I loaded Reed's V1.5.1 back on and calibrated the BFO/VFO once, all is well again. It's a shame this didn't work out because I really liked the way the N8ME/VU2GAO looked and worked, especially the memories. I believe I could calibrate it on Reed's and then load N8ME/VU2GAO software and it would stay working because those values are stored in EEPROM, but I'm not willing to use such broken software.

Joel
N6ALT

Greg,

I'd add separating the sidetone and audio with common connection to the volume control.?

I did that by lifting one and of C and pin 2 of the LM386. Made a connection by lifting one?
end of the C and lifting pin 2 and connecting the C to pin 2 via a 1 meg resistor using a SIP.?

Also, I use a 5-el HPF with attenuation from
about -70dB to -40dB across the AM band.




If interested, I'll send the details via PM...

Well, just realized I didn't finish my previous message.
Here's what I left out...
On my main board C253 is labeled R253.
I didn't remove anything or cut any traces.
I carefully one end of C253 and tack-soldered a lead.
Lifted pin 2 of the LM386 and attached a SIP socket
Tack soldered a 1 meg to the end of the SIP and the
lead to the other end of the 1 Meg.? Adjust 1 Meg if
needed for desired side-tone volume.

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Chuck did you ?ever live in Colorado Springs?