Lower the gain of the two TX IF amps to 11db each.
There is excess gain.
Less pad and less gain.? Why? the higher gain picks up stuff out of band
and adds it to the mix, result is more and greater spurs.? The pad lowers
the carrier to signal as the carrier is leakage around the balanced
mod and filter.
The problem with padding the 45mhz filter was I tried it and no useful effect.
Lowering the gain was more productive and adding a filter to the 45mhz output?
helped as well.? Reason is the 45mhz amp picked up stuff from the power amp
and adds it to the output creating a greater number of products related to
harmonics of the lower bands and the unfiltered products of the higher bands.
The biggest reason is coupling through power leads and current loops in the
ground plane.
Short explanation is too much stuff getting into places it should not be creating
more new stuff.
Simple fixes like changing a resistor or pad does not fix that.
Allison
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Re: Can we start using SUBGROUPS? uBiTX, biTX40, QRPKITS, Original BiTX20, Homebrew, Other?
On Thu, Aug 30, 2018 at 08:43 AM, Chuck WB6GPO wrote:
How about adopting an informal convention of putting a TOPIC PREFIX on the thread title?
Like the already available hashtags that almost never get used?? It is a very good idea.? It just gets lost in the implementation. ? --
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Re: Personal Best Distance, SSB Phone
#ubitx
New Zealand, ssb 3w qrp with the Spanish ILER20. I logged that as an ordinary qso. I was not in the States of course... But in Italy. New Zealand is exactly on the other side of planet earth from my qth. Just let me say that if you hear anything around s9 or more if you use a qrp you can have a qso, of course it will be more difficult during a pile up. So give up FT8 and come back to cw-ssb!
Il 30/ago/2018 16:28, "EI_Frank" < mckeownfg@...> ha scritto: So what's your personal best distance on SSB Phone. I'll kick off with a meagre 380 km's (236 miles). With an End Fed half wave wire on 40m with a uBitx. Who's next. ? 
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Re: Personal Best Distance, SSB Phone
#ubitx
On 6M K9ppy and W4IMD using HB portable rig at 820mW. into the
4 element beam at 33ft.??
For HF:
For 5W using my Argonaut 505 on 40m the best was SV54rwu from W1 country.
For the Slopbucket 20, DL5ARH
These two using LNR EF-quad at 30ft.
For the KNQ7A (40M) VK3 foundation station while mobile (8ft centerloaded whip).
That radio does about 7-8W? at 13.8V.
For 10m during the last solar minimum all of South America, the carib islands,
Falklands and Antartica all using 4W SSB HB into one of two antennas the
PAR EF40/20/10? and the K6STI 10M loop with the top 20ft up.? That was
over a 5 month period.? ?I credit the K6STI 10M loop a 73" wide by 146" high
rectangle for the better part of all that as it was aimed to favor South America.
The par EF40/20/10 as set up then favored east west paths.
Antennas that are oriented in the desired direction and high enough to
be effective seem to make a difference.
Allison
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I'm trying to use the free trial of Gerbview to convert an RS-274D Gerber file to an RS-274X... but I'm a tad lost in the details of doing so - as I'm not experienced at this. I've already paid for a board at a Chinese firm, and even though the money is already spent, I'm currently not getting anything for it!
Anyone here willing to help? Or point me to where I can get some help? (And while free is great, I'm not unwilling to pay...)
73 Ben Holmes, K6QV
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Allison,
I think I said overdriving the mixers is the problem in one of the notes. So how would you go about reducing those drive levels ? Reduce the signal level or increase the LO level.
The 4 dB pad on the input to the 12MHz crystal could be increased, The 6dB pad on the LO's could be reduced to something less. You could add a pad to the 45MHz Mixer input. I don't know if you want to do anything with the last mixer.
In the interests of efficiently using existing parts, how about swapping the 4dB pad (input to the 12MHz section) with the 6dB pad parts on that mixer LO ?
73 Kees K5BCQ
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On Thu, Aug 30, 2018 at 09:31 AM, Gordon Gibby wrote:
Yes, but their ?throughput is very low, and in emergencies, I¡¯m not sure how much vital messaging you can get done with them.....
?
Communications protocols are a trade off
?
?
Gordon
?
Horses for courses.? My wire antenna would make a horrible climbing rope.? Assuming your emergency set up covers multiple bands and includes digital modes I would think getting a quick low power look at propagation would be useful.? That aside, you might be interested in FT8call.? I don't know much about it other than what I've read but it might be useful for your needs ? --
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My opinion only, others will have their own. A remote tuner at the antenna is the best choice as it will have the least loss in your coax. as for automatic vs manual, it is mostly personal taste. In some cases a manual tuner may give a better match than an auto tuner but the auto tuner will work well 99.7% of the time.
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Yes, but their ?throughput is very low, and in emergencies, I¡¯m not sure how much vital messaging you can get done with them.....
Communications protocols are a trade off
Gordon
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The K1JT modes sure do give you a high action to watt ratio.? I have FT8 QSO's between USA and ZL on just over 4w which is 13,176.51km (8,235.318 miles). On my raspberry pi WSPR rig I have reports from ZL as well and that is on
.1w.
--
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Personal Best Distance, SSB Phone
#ubitx
So what's your personal best distance on SSB Phone. I'll kick off with a meagre 380 km's (236 miles). With an End Fed half wave wire on 40m with a uBitx. Who's next. ? 
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The K1JT modes sure do give you a high action to watt ratio.? I have FT8 QSO's between USA and ZL on just over 4w which is 13,176.51km (8,235.318 miles). On my raspberry pi WSPR rig I have reports from ZL as well and that is on .1w.
--
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Re: Nextion 3.2 for CEC 1.097
#ubitx
HI John
I've done all the resizing except page 11 and 0 px which is a little complicated for me .
Nikos SV9CVJ
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Re: Can we start using SUBGROUPS? uBiTX, biTX40, QRPKITS, Original BiTX20, Homebrew, Other?
How about adopting an informal convention of putting a TOPIC PREFIX on the thread title?? For example:
uBitx: How do I connect the Raduino to the main board?
Common prefixes could include:
uBitx:
bitx40:
bitx20:
raduino:
compliance:? <yawn>
etc.
This would make it easy to scan messages for those of interest without the burden of maintaining subgroups.? If the frequent posters adopted this convention, others reading the group would likely catch on.
Just my 2 cents.? I enjoy reading this group, let's keep it fun.
Chuck WB6GPO
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I use an? LDG Electronics Z-11 Pro auto tuner.? It works very well..? - Lee - N9LO? "I Void Warranties"
?
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i find a cheaper? PVC gangs based? antenna tuner kit as sold by ebay.? For QRP? it should be fine. I know of friends who used? PVC gangs for antenna tuners.
regards sarma
vu3zmv
What I am using with bitxs
Raj
At 30/08/2018, you wrote:
>Hi,I? want to add an antenna tuner for my micro bitx. which is the best?? Manual or Auto or Remote ATU? you suggestions and experiences please.
>73,VU3JYT,Rajan
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Come on, it's FT8, 10w and a wire antenna on the roof are more than enough for 13Kmiles SSB/CW contacts, although not everyday . Try that on the upcoming wwssbdx contest.
Il 30/ago/2018 04:20, "Don - KM4UDX" < dontAy155@...> ha scritto: Reach is a function of antenna, and the weirdness of the heavens, etc. etc. etc.? All of 10w.? And so many of you have gone really far. I am but a grasshopper.
But it might be fun to get other distance records?? I was pleasantly surprised to see this.
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Re: Can we start using SUBGROUPS? uBiTX, biTX40, QRPKITS, Original BiTX20, Homebrew, Other?
Very good,
But do follow the progress of the harmonic/spur reduction efforts by the various folks on this forum and if there are some clear cut solutions that settle out, consider them. What would be good is, if Farhan at some point sorts out what may or may not need to be done about the harmonics and such. I'm sure he has the same lab equipment as the other folks looking into these issues and certainly a much bigger sample of boards, enclosures and various construction variations to know if, when and why the harmonics are there. I've seen a few posts where he mentions he is "at the bench". ?
Tom, wb6b
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Re: Can we start using SUBGROUPS? uBiTX, biTX40, QRPKITS, Original BiTX20, Homebrew, Other?
Hello Tom,
Totally agree with you. I am using a uBitx factory mounted and unmodified to date. No modifications to increase the power I chose it as QRP device. The only changes I'm considering: 1) update the firmware 2) remove the 7805 from the display to mount it on a radiator (modification PH2LB) 3) AGC and removal of Rx / Tx clicks (modification (K5BCQ AGC kit) 4) Added a CW / SSB audio filter (Sotabeam) followed by an LM386 audio amplifier for better audio (already tested out of box) 5) Arduino additional ports module to add buttons on the front panel (modification PH2LB) 6) Full SDR receive with G4HUP buffer amp
All the rest may be external addons: ATU, SWRmeter, etc ...
73 QRO Gilles - F1BFU / Fr
Le?jeu. 30 ao?t 2018 ¨¤?08:28, Tom, wb6b < wb6b@...> a ¨¦crit?: I don't know what the regulations are in France, but some folks in the UK have indicated there is no hard harmonic level specification in the UK.?
If that is the case in France, I think you could make a case for the uBITX emissions being reasonable because it is a low power rig to begin with. Just don't hook the uBITX up to another amplifier. And probably you would not want to do some of the various TX increase power mods, unless you can be sure the mod doesn't rase the power while destroying the linearity of the TX chain.
Even here in the US many people might use the same sense of pragmatism. As there are some reports of radios that do indeed meet spec, I don't want to do a bunch of mods unless, one, I can actually verify that they are needed and, two, I can actually verify they fixed anything.?
I live in the US so I'm currently working on and plan to verify what levels of harmonics and other undesirable emissions my radio has and fix it accordingly.?
Tom, wb6b
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Cool! What¡¯s your setup like? Antenna configuration?
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Show quoted text
On Wed, Aug 29, 2018 at 22:20 Don - KM4UDX < dontAy155@...> wrote: Reach is a function of antenna, and the weirdness of the heavens, etc. etc. etc.? All of 10w.? And so many of you have gone really far. I am but a grasshopper.
But it might be fun to get other distance records?? I was pleasantly surprised to see this.
-- Adam Goler, PhD Cell: (425) 985-8700
"Fear is the mind killer."
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What I am using with bitxs
Raj
toggle quoted message
Show quoted text
At 30/08/2018, you wrote: Hi,I want to add an antenna tuner for my micro bitx. which is the best? Manual or Auto or Remote ATU? you suggestions and experiences please.
73,VU3JYT,Rajan
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Frank_EI8HIB
SV9CVJ Nikos
Lee
Raj vu2zap