Date   
Re: Calibration needed ? #calibration #v6

Evan Hand
 

Belthur,

Reading between the lines of your post I will assume that you are operating SSB below 10 MHz, lower sideband (LSB), on a v6 uBiTx. 

The issue that is reported to you is that your output signal is bleeding into the upper sideband (USB).  This can be caused by the BFO not in alignment with the SSB filter.  It can also be caused by overdriving the audio input on the rig.

The procedure that Ashhar Farhan outlines in the video post is the correct one for the alignment of the BFO.  Just be careful to go more towards the 3 KHz red marker than the 500 Hz for the BFO adjustment.  As Reed stated, it will sound a little tinny.

Monitoring your signal is the only way short of a spectrum analyzer (SA) to verify your output signal. To check your own signal, you might want to find a Web-based SDR  site to monitor for yourself.  There are a number of them around the work listed at
http://www.websdr.org/
Find one in an area where you have received the bleed issue report if possible, otherwise one that can hear your transmission.

If you do want to go the SA route, I have been having good results recently with an RSP2 SDRPlay.  They no longer make that model, however, the specifications of the RSP1a are better and list price is currently $109 US.  The SA software is free and is now able to do all of the signal purity measurements that the prior releases could not. You will also need a directional tap. I made one from this article: 
http://www.ad5x.com/images/Articles/Tap50dbRevA.pdf
And a step attenuator like this one:
https://www.ebay.com/itm/NEW-0-82DB-VARIABLE-STEP-ATTENUATOR-OHM-for-Ham-Radio-Transmitter-DC-to250MHZ/183306489164?hash=item2aadeb0d4c:g:~scAAOSwCTBbPGyN
So far this is the lowest cost approach that I have found for a SA.  The total cost including all parts, adapters, and cables should be less than $200 US, less if you shop around.  There is a homebrew SA built with parts from eBay that I plan to try.  I do not recommend an RTL-SDR dongle, the RF Explorer, nor the Analog Discover 2.  I have tried all three and they have not produced results that are consistent or require multiple setups to do the harmonic tests.  This is not the case that others have reported, so it may be that I do not have the correct setup for them.

Above are just suggestions, you are responsible for the signal purity of your radios.
73
Evan
AC9TU

Re: Find an older style Raduino #raduino

 

There seem to be many Raduino PCB patterns in the files section here.

73,


Mark

Re: BITX 14MHz Build #bitx20

 

Hi Aaron,

I not used MeSquares, but have done quite a bit of "dead bug" construction (which is just placing parts - upside down or not - over an unetched PCB).  Basically I just follow the schematic as it pretty much already organizes the parts in the place you want them on the board.  Start with the receiver antenna connector (or short piece of coax or twisted line) and just start building out.  The receive bandpass filter is first, then the RF amp, mixer, etc all follow.  The build will probably end up long an narrow, but that is good as it keeps the higher level signals away from the lower level ones.  Reading the description of Farhan's build you will see he did it this way too.  You might want to build the VFO, BFO, and AF amp on separate PCB's.  This will allow you to shield the RF one's and also allow you to keep the build from getting too long.  For sure I would put the PA on a separate board.

When soldering parts to the ground plane, remember that is one big piece of copper that you are heating up.  It will take higher heat and a longer heating time than the parts.  Clean then wet the tip of the iron with fresh solder, place the tip on the board where you want to solder, and wait until solder placed on the PCB near the tip will melt by itself.  Then you can place the part to be soldered to it onto the board.  This will keep the part from over heating.

You can place parts upside down or rightside up -- whatever is easiest and makes connections the simplest.

73,


Mark

PS:  Ferrite core toroids or old TV baluns will work much better than tap washers for transformers and inductors as the designer found out in the end.

PSS: If you can't find Toko type transformers for the bandpass filter, you can use fixed inductors and accomplish the filter adjustment by making the capacitors variable instead (trimmer caps). 

Re: Heatsink question #v6

Don - KM4UDX
 

Tom -- many uBITXers have faced the same issue...digital modes...long duty cycle...heat...

My approach was to hacksaw larger heatsinks from an old Pentium computer motherboard's CPU.  They have a lot of heatsink!  I then drilled a new hole in about the right position. Screwed the 510 to them and immediately realized that I failed to pay attention in class. If you just screw'em together like I did, they can't touch anything...at all...even air might be a risk...just kidding...  But, if they socially isolate, and ho hand holding, then you can cook'em up.

Better to do as other suggest: Use electrical isolation. 

The good news here...is if you add some mondo head sink, and/or fan...then you can use a old laptop 19v (typical for dells, etc.) powersupply to drive the (red..or...brown?) wire on the little power connector to the mother board that drives the finals (only).  That will feed the 510s with (typically) 19.5 volts, and you will (almost) double your juice out the antenna.  If you have a old 24 volt power supply sitting around...welll...then you will definitely 2x your juice...and make your uBITX a real groovy hot rod. yeeehaaa.

Here are some pics of the salvaged heat sinks next to the originals, and a pic of them installed.  Yes, they practice social isolation. hahah. 

I eventually cut a hole behind the heatsinks and added a fan. I did that after my original IFR510s went all Chernobyl on me under...wait for it...too much heat...hahaha. 

While I am clearly a slow learner, the mighty uBITX has stood up to the abuse. 

Re: BITX 14MHz Build #bitx20

Jason Pirok
 

W2AEW (Alan Wolke) has a great video on the layout of Manhattan style PCB building. 

This one illustrates the island method, but the techniques can be used for Manhattan.
https://www.youtube.com/watch?v=blalAktxFoI  

This one goes over several other construction techniques.
https://www.youtube.com/watch?v=kH110yjYZ2g  

--
Jason Pirok
W4UNX

Re: Find an older style Raduino #raduino

Jason Pirok
 

Jim, any chance you could share the PCB file with the group? At least that would be a starting point for those who would like the older Raduino?

--
Jason Pirok
W4UNX

Re: BITX 14MHz Build #bitx20

Arv Evans
 

If you are not using a Bitx pcb, then your question is questionable.  Build instructions are for using a bitx pcb.  For one-off builds using manattan or ugly method you just need to decide your own layout and construction sequence.

Arv. K7HKL
_-_


On Tue, Apr 7, 2020, 6:58 AM Aaron Scott via groups.io <k5atg=yahoo.com@groups.io> wrote:
Hello everyone,
I'm going to start building the BITX 14MHz build. It's going to be my first homebrew transceiver project so I will be learning as I go. The instructions say to solder the transistors first but since this is my first go around, I'm not really sure where I should put them on the PCB. I'm going to use Manhattan construction using the QRPme Little MeSquares. So if anyone has any tips or pointers for a newbie, I will be greatly appreciated.  

One possible substitute for a Spectrum Analyzer's "Tracking Generator" #ubitx

Jim Sheldon
 

I got an email from a trusted friend this morning with some very interesting information for those who have spectrum analyzers that do not have tracking generators, or the new versions of inexpensive VNA's like Ashhar's "Antuino" or the NanoVNA which have sweep functions but I'm not sure exactly how they work in this respect.

Below is a link to a site that explains how to use a reasonably inexpensive wide band noise generator as a substitute for the tracking generator.  Short article that goes into enough detail to help you get started and the second link is to a possible source (eBay - there may be others as well) for the generator itself.  If the links don't work, cut and paste them into your browser's address window.

One possible source of the noise generator: 
https://www.ebay.com/itm/0-2-2000M-Noise-Signal-Generator-Noise-Source-Simple-Spectrum-Tracking-Source-US/263993828638

This info may help some of you with BFO alignment on your uBITX.

Jim Sheldon, W0EB

Re: uBitx V5 can't make a contact on ft8

McRuss
 

I'm still waiting for an antenna adapter for my V6 but am interested in setting it up for FT8.  So exactly how did you disconnect the PTT connection on the dongle?
I'm not sure how the dpdt switch is connected or when you would activate it.  Sorry for being such a dummy.

Russ
K5FJR

Re: Heatsink question #v6

BruceN
 

I might mention that if you have some old junk PC power supplies, you can salvage these isolation kits from them.  These supplies have several transistors isolated from their heatsinks.  At 3 bucks apiece new, getting these is worth the effort.  You can find junk power supplies at almost any computer repair shop or Habitat Restores and secondhand shops that have old PC's.  I've a good supply of isolation kits from salvage.  Just remember to use some thermal paste.

BruceN / K4TQL
--
"To invent, you need a good imagination and a pile of junk"  -- Thomas Alva Edison (1847-1931)

Re: Find an older style Raduino #raduino

Jim Sheldon
 

Thanks Jason, but for everyone's info, I do not have any more old style Raduino's around here.  Jason got the last one I had, sorry.

Jim, W0EB

------ Original Message ------
From: "Jason Pirok" <jason.pirok@...>
Sent: 4/7/2020 6:44:14 AM
Subject: Re: [BITX20] Find an older style Raduino #raduino

Your best bet is if Jim W0EB (I believe) has any left. I purchased one he had left over, but not sure if he has another. I found something that looks like another original Raduino clone on Ebay, but I am skeptical. It is pretty slim pickings for them right now. At worst you may need to have some PCBs made and build it yourself if you have that skillset/materials/time etc.

--
Jason Pirok
W4UNX

BITX 14MHz Build #bitx20

Aaron K5ATG
 

Hello everyone,
I'm going to start building the BITX 14MHz build. It's going to be my first homebrew transceiver project so I will be learning as I go. The instructions say to solder the transistors first but since this is my first go around, I'm not really sure where I should put them on the PCB. I'm going to use Manhattan construction using the QRPme Little MeSquares. So if anyone has any tips or pointers for a newbie, I will be greatly appreciated.  

Re: uBitx V5 can't make a contact on ft8

_Dave_ AD0B
 

How has it worked on phone?

As a ham we are required to have control of our signals. Owning a radio is a start but you need to have an idea of it's power output Even a simple CB quality SWR/Power meter can give you an idea. 
--
73
Dave
ADOB
Raduino bracket and Ham_Made_Keys

Re: Find an older style Raduino #raduino

Jason Pirok
 

Your best bet is if Jim W0EB (I believe) has any left. I purchased one he had left over, but not sure if he has another. I found something that looks like another original Raduino clone on Ebay, but I am skeptical. It is pretty slim pickings for them right now. At worst you may need to have some PCBs made and build it yourself if you have that skillset/materials/time etc.

--
Jason Pirok
W4UNX

Re: uBitx V5 can't make a contact on ft8

Mick
 

Gavin,
I also have the same antenna as you do, mine is about 25’ in the air. I‘M making FT8 QSO’S all over NA and the odd EU as well. I also found an antenna tuner works well with this antenna despite what the manufacturer says about matching.
--
 

73
Mick VA3EPM 

Re: uBitx V5 can't make a contact on ft8

Curt
 

Gavin

At that height your radiation will mostly be straight up. The ground connection should matter little for radiation,  its to bleed off static charge to prevent rig damage. I sometimes use an EFHW at about 30 feet for its middle, but generally use my vertical antenna for 40m ft8 and ft4. With the heavy qsb we experience now, its not easy to make ft8 contacts unless the band is propagating well. Sometimes you can't qso a few hundred miles but then you contact many thousand miles. Learn about antennas and improve to what you fan erect there. late in Spring watch for 10m E skip, build a 10m dipole, moxon or quad.

Curt wb8yyy

Re: uBitx V5 can't make a contact on ft8

Mick
 

Gavin,
I agree with Scott’s antenna suggestion. Another improvement I discovered was to use a USB dongle sound device (see below, the one I use) The sound volume and quality are greatly improved compared to direct to computer connection.
You will have to make sure the PTT connection from the dongle is disconnected or it will constantly trigger your TX.
I eventually mounted a second set of 3.5mm jacks on the back of my rig (wired to the audio jack) through a selector switch (Dpdt on-off-on) on the front of my rig.


--
 

73
Mick VA3EPM 

Re: #firmware #i2c #smeter #ubitx #calibration #calibration #firmware #i2c #smeter #ubitx

Vic WA4THR
 

Elecraft has (or used to have) a simple S-meter calibrator that put out a signal that was supposed to be S9 and was pretty inexpensive, if you really need to have accuracy. Then you could check it with another station adjusting their power remembering that each S-unit represents 4X the power (or double the voltage if you are measuring that). If it needs changing you will have to reprogram the second Nano. Having an S3 all the time is about right, that is typically the level of band noise. It should go to zero if the antenna is disconnected. As I said before, with the second Nano mine is agreeing pretty well with a commercial rig in the shack except for the timing as it is a bit slower to respond.

=Vic=

Re: uBitx V5 can't make a contact on ft8

KN4SMO
 

Hello Gavin,
Certainly you will have a better experience if you can get you antenna up, as high as possible.  I am a beginner as well.  My antenna performed great when I was able to get it up 50 to 60 feet in the air.

Good Luck Scott

On Mon, Apr 6, 2020 at 11:45 PM Gavin <gdesplin@...> wrote:
I just got things set up to try to do some FT8 with my uBitx v5. I am new to HF in general and have yet to make a QSO.
I can receive fine, but pskreporter.info says only 6 reports for my about an hour session tonight, all a in the same state a couple states away. To get that I had to get my computers clocked synced up as it was a couple seconds off. I am using CAT control and two simple audio cables from a usb sound card directly plugged into mic and phone on my radio, which is running off power from a 12v SLA battery.
My antenna is a MFJ-1984LP EndFed 1/2 Wave strung up 12 ft about in the air from a tree to my pergola, slightly sloping up. I have it grounded as well. This is my best guess as the problem, but I've heard others on here get much better results with similar setups I think. Its supposed to be a no-tune antenna, but I have no swr meter to confirm it has a low swr level like its supposed to.

Anyone have any tips or ideas? I'm a brand new beginner at all this. Thanks very much.

Re: Calibration needed ? #calibration #v6

Reed N
 

Oh, and here's a link to the thread with some of my investigating and experimenting:

https://groups.io/g/BITX20/topic/bfo_calibration_and_ssb/70940600


Reed