Another cool thing is you can record yourself for playback, an easier comparison than trying to listen to yourself after a short delay. I know when I try to listen myself directly I get confused.
Bill has a good point about lobes, you can check your performance at multiple sites to get a better idea of where each antenna works best.
73
Whiskey Sours 4 Jumping Monkeys
Jay
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Re: Spurs/Harmonics fixes for v4 based on v5 board design?
Ah Thanks.? Ok I guess I still have a lot to learn about desoldering :) The needle is an interesting idea.? If I was going to do a lot of through hole desoldering I would probably try that hakko vacuum tool - kind of expensive though if you don't do it that often looked like it did a nice job though from the video's I saw.
Luckily I was using a really small bit that didn't take the full hole size so hopefully didn't do any major damage.?
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Exactly it is sensitive enough as tabletops or portables (degen 1103, Sangean 909 etc). The difference may be in other characteristics, like blocking, the presence of BPF, signal handling, but as for sensitivity it is very hard to find a real deaf one if everything is functioning well.
Il 25/gen/2019 09:12, "Lawrence Galea" < 9h1avlaw@...> ha scritto: Agree. That's why I set the R8 without a preamp like the ¦Ìbitx. Re more audio on the R8 it was to explain on the different audio levels between the two receivers and a hint for those who would like more audio but with headphones should be ok on marginal signals.
As you said noise is the limiting factor on the lower frequencies and adding an amplifier will not only boost the signal but also the background noise.
However, it may, in relatively quiet locations, give a better copy as it may override the receiver internally generated noise and other losses within the receiver.
it would be interesting if someone who may have changed the receiver first 45 MHz IF section with hotter / lower noise transistors to report on the result. Regards Lawrence
On Fri, Jan 25, 2019 at 12:24 AM Curt via Groups.Io <wb8yyy= [email protected]> wrote: Lawrence
Good data!? Please notice that sensitivity relates to our ability to copy a signal in the background (and rig supplied) noise -- not how much audio the receiver can pump into the air.? yes I perceive you already agree.?
how a receiver changes with preamp on and off does vary with how gain is built into the receiver.? a receiver can be 'gain limited' - meaning more gain would improve sensitivity or 'noise limited' - which you can guess means more gain does not improve sensitivity.?
depending upon our latitude, season etc. the background noise does vary.? at lower HF there is more noise in the atmosphere than our receivers can make, this only changes at the upper part of the spectrum.? in a quiet area with little man-made noise it will be interesting to compare the uBITX to receivers having a preamp on 28 MHz.? I am expecting only a small difference, less than one S-unit maybe.
likely many already know this, but QRN is propagated via the ionosphere - often from tropical regions.? cool stuff!
73 Curt
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Hi get a long bolt, use a nut washer and spring washer to fix it to the case, then use another nut etc adjusted to the level of the other standoffs and use another nut etc to lock the pcb. Regards
I've been admiring my bitx40 for a while, nice looking board.
Finally, I knuckled under to build it and found a couble of problems.
?
1. no mike.
?
2. One standoff has no threads - it happens.
? ? Furthermore, it?could use about 2x as many standoffs. (The Radino should not be connected solely with ribon cable.)
?
What do I need to do?
?
m
78
?
?
|
Agree. That's why I set the R8 without a preamp like the ¦Ìbitx. Re more audio on the R8 it was to explain on the different audio levels between the two receivers and a hint for those who would like more audio but with headphones should be ok on marginal signals.
As you said noise is the limiting factor on the lower frequencies and adding an amplifier will not only boost the signal but also the background noise.
However, it may, in relatively quiet locations, give a better copy as it may override the receiver internally generated noise and other losses within the receiver.
it would be interesting if someone who may have changed the receiver first 45 MHz IF section with hotter / lower noise transistors to report on the result. Regards Lawrence
On Fri, Jan 25, 2019 at 12:24 AM Curt via Groups.Io <wb8yyy= [email protected]> wrote: Lawrence
Good data!? Please notice that sensitivity relates to our ability to copy a signal in the background (and rig supplied) noise -- not how much audio the receiver can pump into the air.? yes I perceive you already agree.?
how a receiver changes with preamp on and off does vary with how gain is built into the receiver.? a receiver can be 'gain limited' - meaning more gain would improve sensitivity or 'noise limited' - which you can guess means more gain does not improve sensitivity.?
depending upon our latitude, season etc. the background noise does vary.? at lower HF there is more noise in the atmosphere than our receivers can make, this only changes at the upper part of the spectrum.? in a quiet area with little man-made noise it will be interesting to compare the uBITX to receivers having a preamp on 28 MHz.? I am expecting only a small difference, less than one S-unit maybe.
likely many already know this, but QRN is propagated via the ionosphere - often from tropical regions.? cool stuff!
73 Curt
|
Re: Spurs/Harmonics fixes for v4 based on v5 board design?
I agree that the drill is a bad idea because it might drill out the plated-through hole. I have an old ice pick that serves me as would a darning needle. It's iron and the
solder does not stick to it.
On Thursday, January 24, 2019, 11:14:34 PM EST, Jerry Gaffke via Groups.Io <jgaffke@...> wrote:
Bad idea to drill out the solder in those holes.
Tim's darning needle is a much better idea.
Those holes are plated through, a vertical cylinder of metal plating added to the hole during board fabrication
that connects traces on the top to traces on the bottom.? If the drill is too big, you will cut that connection.?
??
Jerry
On Thu, Jan 24, 2019 at 07:01 PM, Timothy Fidler wrote:
If you heat up the covered copper land and thrust in a darning needle , say 1.5mm diameter,? you can forget? the jeweller's drill.? Solder will not stick to chrome plate.
?
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Re: Spurs/Harmonics fixes for v4 based on v5 board design?
Bad idea to drill out the solder in those holes.
Tim's darning needle is a much better idea.
Those holes are plated through, a vertical cylinder of metal plating added to the hole during board fabrication
that connects traces on the top to traces on the bottom.? If the drill is too big, you will cut that connection.?
??
Jerry
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Show quoted text
On Thu, Jan 24, 2019 at 07:01 PM, Timothy Fidler wrote:
If you heat up the covered copper land and thrust in a darning needle , say 1.5mm diameter,? you can forget? the jeweller's drill.? Solder will not stick to chrome plate.
?
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I took the electret unit that came with the bitx 40 kit and the push button and mounted them in a piece of 3/4 pvc pipe and it works very good.? Mine also had a standoff with no threads. The bitx 40 works extreamly well. Good luck.? Dave? kc2ipx
Martin,
Just to double check, the mic is just an electret mic like the picture below.? I don't have one in front of me to measure but it is approximately 10mm in diameter.
--
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Re: Spurs/Harmonics fixes for v4 based on v5 board design?
If you heat up the covered copper land and thrust in a darning needle , say 1.5mm diameter,? you can forget? the jeweller's drill.? Solder will not stick to chrome plate.
? Timothy E. Fidler : Engineer BE Mech(1) Auckland , NDT specialist AINDT UT /RT3 , MT2 CB #2885,?
Telephone Whangarei?? 022? 691 8405
e: Engstr@...
----- Original Message -----
To: <[email protected]>
Cc:
Sent: Thu, 24 Jan 2019 16:33:43 -0800
Subject: Re: [BITX20] Spurs/Harmonics fixes for v4 based on v5 board design?
Yep I just figured I would do the rest for good measure... though didn't realize how bad I was at desoldering.
To amend my previous statement it took vaccum desolderer, braid and a jewelers hand drill to clear out the holes to make it easier to get the new ones in.? I'm sure there other possibly easier ways but I chose the hard one.? ?I'm slightly better at desoldering now though :)
On Thu, Jan 24, 2019 at 06:24 AM, Raj vu2zap wrote:
Only three relays need to be replaced KT/1/2/3
Raj
At 24-01-19, you wrote:
I will also say you will have to perfect your desoldering skills to remove all 5 relays :)? I thought I knew how to desolder before I started... but clearly I was deluding myself.
I nearly gave up but watched a couple youtube video's and so someone much better than I doing it and managed to learn the way to do it with a simple suction vac and desoldering braid.. though I was really wishing I had one of those hakko electric vacuum desoldering tools :)
On Tue, Jan 22, 2019 at 06:55 PM, Dave Space wrote:
- I actually did replace all of the relays with axicom relays.? I bought some parts to build an external filter to see how that does (not due to arrive for a while).? I'm transmitting SSB when doing the test.
- I also bought the parts to replace L5 and L7 not due to arrive for a little while either.? Any chance the mod suggested for the v5 board would solve this harmonic?
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Ok thank you David I'm waiting for your answer, I saw this support in a post with k8cec and the laserbeam over, it thanks jo?l f6cht.
Le 24/01/2019 ¨¤ 20:18, N8DAH a ¨¦crit?:
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Joel,
?I will send you a email so we can sort it out. While this is not
a item I stock we can work something out.
--
David
?N8DAH
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Re: Spurs/Harmonics fixes for v4 based on v5 board design?
Yep I just figured I would do the rest for good measure... though didn't realize how bad I was at desoldering.
To amend my previous statement it took vaccum desolderer, braid and a jewelers hand drill to clear out the holes to make it easier to get the new ones in.? I'm sure there other possibly easier ways but I chose the hard one.? ?I'm slightly better at desoldering now though :)
toggle quoted message
Show quoted text
On Thu, Jan 24, 2019 at 06:24 AM, Raj vu2zap wrote:
Only three relays need to be replaced KT/1/2/3
Raj
At 24-01-19, you wrote:
I will also say you will have to perfect your desoldering skills to remove all 5 relays :)? I thought I knew how to desolder before I started... but clearly I was deluding myself.
I nearly gave up but watched a couple youtube video's and so someone much better than I doing it and managed to learn the way to do it with a simple suction vac and desoldering braid.. though I was really wishing I had one of those hakko electric vacuum desoldering tools :)
On Tue, Jan 22, 2019 at 06:55 PM, Dave Space wrote:
- I actually did replace all of the relays with axicom relays.? I bought some parts to build an external filter to see how that does (not due to arrive for a while).? I'm transmitting SSB when doing the test.
- I also bought the parts to replace L5 and L7 not due to arrive for a little while either.? Any chance the mod suggested for the v5 board would solve this harmonic?
|
Martin, Just to double check, the mic is just an electret mic like the picture below.? I don't have one in front of me to measure but it is approximately 10mm in diameter.  --
|
Martin
scrounge whatever hardware you can for assembly.? if you don't like this plan, there are several fine suppliers of cases aka enclosures available.?
if you have a 'surplus. electret based microphone - try it out.? I am using something once used with an HT I no longer have.? use a search engine here or on the web to see what others are using with the BITX.? Pacific Antenna in US has a microphone kit for these rigs - but its nothing you can't homebrew from the electret microphone furnished with the kit or available on ebay etc.?
do enjoy assembly of the fine rig.? the beauty is having it your own way as you assemble it, and a wealth of ideas from a world-wide community of builders.?
Curt
|
Lawrence
Good data!? Please notice that sensitivity relates to our ability to copy a signal in the background (and rig supplied) noise -- not how much audio the receiver can pump into the air.? yes I perceive you already agree.?
how a receiver changes with preamp on and off does vary with how gain is built into the receiver.? a receiver can be 'gain limited' - meaning more gain would improve sensitivity or 'noise limited' - which you can guess means more gain does not improve sensitivity.?
depending upon our latitude, season etc. the background noise does vary.? at lower HF there is more noise in the atmosphere than our receivers can make, this only changes at the upper part of the spectrum.? in a quiet area with little man-made noise it will be interesting to compare the uBITX to receivers having a preamp on 28 MHz.? I am expecting only a small difference, less than one S-unit maybe.
likely many already know this, but QRN is propagated via the ionosphere - often from tropical regions.? cool stuff!
73 Curt
|
I've been admiring my bitx40 for a while, nice looking board.
Finally, I knuckled under to build it and found a couble of problems.
?
1. no mike.
?
2. One standoff has no threads - it happens.
? ? Furthermore, it?could use about 2x as many standoffs. (The Radino should not be connected solely with ribon cable.)
?
What do I need to do?
?
m
78
?
?
|
Hi This morning I had an hour to spare so I switched on the ¦Ìbitx and there was good propagation on 18 MHz.
So I switched on the Drake R8 to compare the signals. The R8 agc was set to off as the ¦Ìbitx does not have agc, preamp off as the ¦Ìbitx does not have an RF amplifier, and the bandwidth set to 2.3 kHz. I swapped the antenna between the two sets several times and made a video which I uploaded on youtube.
In the video you may notice some difference on the digital readputs because I had initially not set the two sets on exactly the same frequency during the video , but later on I set both on the same frequency and they both tallied 100%.
As regards sensitivity both appeared to be approximately the same with the R8 having a slight edge on the ¦Ìbitx and obviously greater audio output of the R8 which was set at approximately half way while the ¦Ìbitx volume was full on.
Those wanting more audio could get one of the cheap available amplifiers such as
1x 2x18W TDA2030A 2.0 Double Track TDA2030A Audio
Amplifier Board Module X4Z5 US $5.27
PAM8403 2 Channel USB Power Audio Amplifier Module Board
3Wx2 Volume Control US$1.59
5pcs PAM8403 Miniature Digital USB Power Amplifier Board
2.5V - 5V US$2.67
15W TDA7297 Dual-Channel Amplifier Board For Arduino US$3.92 US$1.63 via Air
Parcel Registe
3Pcs TDA2030 TDA2030A Audio Amplifier Module US$3.70 US$1.59
via Air Parcel Register Enjoy Regards? Lawrence
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?BITX-RSP1A-FT8 &c Mashup
The ?BITX is working well on FT-8!
?
Now it has a QRP Kits Easy TR Switch flipping between the ?B for TX and a SDRplay RSP1A on SDRuno for RX.? The WSJT-X software controls the ?B via USB using KD8CEC's FT-817 emulation feature.? WSJT-X listens to the RSP1A using Virtual Audio Cable.? Ian's calibration provision gets the ?B and RSP1A to agree within 3 Hz on 15M.
?
https://www.qrpkits.com/ezseries.html#eztrsw
?
https://www.sdrplay.com/rsp1a/
?
https://www.vb-audio.com/Cable/
?
Ian's also got a way to use SDR to control the VFO on the ?B:
?
http://www.hamskey.com/2018/04/how-to-connect-sdr-rtl-sdr-to-ubitx-and.html
?
So the question to this esteemed group is:
?
Has anyone here managed to use WSJT-X to control both the ?BITX and some SDR receiver?
?
There might a couple of routes.? One is the WSJT-X controls both.? Another would be the WSJT-X tells the ?B what frequency to use, then the ?B tells the SDR where to go.? The third would be to have the WSJT-X to tell the SDR, then the SDR tells the ?B, kinda like Ian's approach.
?
Thanks!
|
Hi Gary,
Your antenna comparison did not take into account where each antenna have it's lobes. For some stations one will work better and for other stations the opposite one will be better. It depends on direction and elevation of the arriving signals. You have little or no control over any of that. Even with yagi beams it can vary.
Keep both antennas:)
73,
Bill KU8H
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Show quoted text
On 1/24/19 2:42 PM, Gary Hanson wrote: A couple of days ago I had an interesting qso with K9BHP (Ben) using my ubitx.? Ben called CQ on 20 meters from Chicago and I answered him with my ubitx running at 7 watts from Austin, TX.? He gave me a report of S7-S8, but mentioned that he could not hear me on his antenna in Chicago, but was using a websdr receiver in Northern Utah.? We chatted for 10-15 minutes and afterward I looked into the websdr receiver that can be found at this URL: websdr2.utahsdr.org <>.? I realized that this wedsdr receiver could be used for several fun things.
First, you can use it to hear your own signal.? Find a clear frequency on the websdr, set your ubitx to the same frequency and call CQ.? If you are getting out, you should hear your own voice, with a slight delay, coming back on your computer. The websdr has a? S-meter so you also can learn what your signal strength is as well.
I used the websdr to compare how well two different antennas were working.? I compared the signal strength of my 88 foot doublet fed with ladder line at 35 feet and an Emtech Z-match tuner with a sloper dipole fed with 50 ohm coax, no tuner and no balun with the feed point at 16 feet.? Interestingly, the sloper dipole signal strength was a little more than 1 s-unit better even though it was only half as high as the doublet.? I suspect that I have a lossy tuner.
Another interesting comparison you could try, but I have not (yet), is to listen to two different microphones to check audio quality and signal strength differences.? At least you would get a chance to hear what the other end of the qso is hearing.
There are more than 65 websdr stations scattered across the world, with several in the US (go to websdr.org <>).? While you can check your propagation with some of the digital modes, the websdr allows you to listen to your audio.? It's just another fun way to play with your ubitx.
Hope you have as much fun with it as I did.
Gary, KJ5VW
--
bark less - wag more
|
A couple of days ago I had an interesting qso with K9BHP (Ben) using my ubitx.? Ben called CQ on 20 meters from Chicago and I answered him with my ubitx running at 7 watts from Austin, TX.? He gave me a report of S7-S8, but mentioned that he could not hear me on his antenna in Chicago, but was using a websdr receiver in Northern Utah.? We chatted for 10-15 minutes and afterward I looked into the websdr receiver that can be found at this URL:? .? I realized that this wedsdr receiver could be used for several fun things.
First, you can use it to hear your own signal.? Find a clear frequency on the websdr, set your ubitx to the same frequency and call CQ.? If you are getting out, you should hear your own voice, with a slight delay, coming back on your computer. The websdr has a? S-meter so you also can learn what your signal strength is as well.
I used the websdr to compare how well two different antennas were working.? I compared the signal strength of my 88 foot doublet fed with ladder line at 35 feet and an Emtech Z-match tuner with a sloper dipole fed with 50 ohm coax, no tuner and no balun with the feed point at 16 feet.? Interestingly, the sloper dipole signal strength was a little more than 1 s-unit better even though it was only half as high as the doublet.? I suspect that I have a lossy tuner.?
Another interesting comparison you could try, but I have not (yet), is to listen to two different microphones to check audio quality and signal strength differences.? At least you would get a chance to hear what the other end of the qso is hearing.
There are more than 65 websdr stations scattered across the world, with several in the US (go to ).? While you can check your propagation with some of the digital modes, the websdr allows you to listen to your audio.? It's just another fun way to play with your ubitx.
Hope you have as much fun with it as I did.
Gary, KJ5VW
|
Vic,
? ?You can retrieve a bezel pattern for any of the Nextion displays from 3.2 through 7 inches from Itead:
? I had a bezel printed by a vendor via 3D Hubs:
? Best,
? ?Andy, KG5RKP
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Jay - WS4JM
Bob Lunsford
David Nelson
Joel Fournol
Arvo W0VRA