Iz
I would start with a pair of fixed-gain op-amps to bring the voltage up to where your test equipment
can measure it reliably.
Arv? K7HKL _._
Good piece of information. How can I measure 50mV in the audio frequencies? I have a Velleman 0-100mV 1khz audio generator kit, but a cheap multimeter does not show a thing. I hope I don't need an oscilloscope or an SA for measuring it...
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Re: Sending perfect CW via PC
Brutus, I have rechecked. And I stand corrected: the simple optoisolated interface (4N25 and usb-serial converter) works perfectly too. Evidently, when I checked this before, an audio jack adapter was not doing a good contact. Damn!
Il 05/mar/2019 15:56, "Brutus Laurentius" < markhamfarm14@...> ha scritto: I wired my ubitx for a straight key so I could use my preferred (AA0ZZ Ezkeyer from 4SQRP) keyer with it.? Later, for fun, I tried interfacing it via a simple 4N25 for DTR via USB serial keying, and it worked fine.? Ditto for a winkeyer clone.? ?I think the difference is that I had wired mine for a straight key in the first place?
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Re: New V5 with poor carrier suppression.
Different radio, different design. But on my early Bitx40 the PCB pads were there for two diodes and a pot. The Bat54 was fitted in place of them. I don¡¯t remember how much but I had quit a bit of carrier. After removing the Bat54 and installing two rendom 1n4148 diode and some small value pot from the junk box I was able to null the carrier to 0.?
I can just say it worked for me.?
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Good piece of information. How can I measure 50mV in the audio frequencies? I have a Velleman 0-100mV 1khz audio generator kit, but a cheap multimeter does not show a thing. I hope I don't need an oscilloscope or an SA for measuring it...
Il 07/mar/2019 07:35, "Ashhar Farhan" < farhanbox@...> ha scritto: the ubitx has more gain on tx as well as rx than the previous boards. this is due to the BFR93w transistors in the 45 MHZ IF in place of the 2N3904s.? The carrier and spurs will be appear to be higher if the tx gain (controlled by RV1) is running flat out. it is best to reduce this to about 60% of the full gain. A way to know this is to connect a 50 mv audio signal to the mic, transmit SSB on 7 MHz and reduce the power until it is around 7 watts.
- f
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Thanks will check and reply.
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Subhash,
L2 is not properly soldered, check continuity on the board and resolder. If that does not help
check L1.
Raj
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At 08/03/2019, you wrote: I am trying to fix the recieve on my bitx40 but it wont recieve until i touch the L2 coil near the relay. I dont know whats the problem. Help would be greatly appreciated.
Regards
VU3EDU
SUBHASH HERUR
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Others like myself have wished for a TFT file for the 3.5" Nextion screen that fills the whole space. While there are a few out there, they don't mirror the "original" format that we know and love (CEC version).?
This is a work in progress though it seems to work well enough to share for further tweaking.? I'm no programmer per se though by using some graphic arts thinking, I've put together the attached. There are a few little errors here and there, so, if you know more than I do or have learned something I've not fell over yet, please feel free to add corrections or tell me how to correct it.? For instance: on the page for recalling a memory entry to VFO, there is a button that should say, "READ" (top row, left of the Frequency mask). The active button is there but it's behind the background fill picture, and needs to be brought to the foreground.
This started as the widely-available "3.5" screen file that doesn't fill a 3.5" screen, and was manually increased by 150% on the horizontal axis and by 133.3" on the vertical, picture by picture and block by block, with things shifted around for spacing and fit - and the font sizes increased in most cases.? It pays to be anal-retentive and O.C.D. just sometimes.
Have fun!
Ted
K3RTA
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Re: AGC Pre-Oders are in and built!
I have ordered the AGC board and looks to arrive on Monday. I will let you know if it will work. Comparing my v5 board to a V3 board it is the same size and layout so it should work. That¡¯s my hope. Will let you know for sure Monday.?
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On Mar 8, 2019, at 12:38 AM, knightsbdh@... wrote: Hi Tim
I have a v5, am happy to test. Send me the file to print and I'll take some photos.
Cheers
Ben
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I am trying to fix the recieve on my bitx40 but it wont recieve until i touch the L2 coil near the relay. I dont know whats the problem. Help would be greatly appreciated.?
Regards?
VU3EDU
SUBHASH HERUR
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Jerry,
See message # 66087
Raj
At 07/03/2019, you wrote:
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This is a critical bit of
information regarding how best to set up a uBitx,
should be in the hfsignals description of the uBitx.
Many here are just turning up mike gain and/or RV1 for max power,
having no idea that this results in a disproportionate increase in
harmonics and spurs.
Does this bit of advice (50mv of audio for 7 Watts out at 7mhz, RV1 at
60%) also apply to the v3 and v4?
I assume you mean 50mv RMS of audio, perhaps at 1khz?? (So RMS, not
peak, not peak-to-peak?)
And that one should not twiddle mike gain or RV1 when moving to other
bands, even if power drops off some.
Ideally, the uBitx would have a way to generate this audio from a digital
IO pin and a couple resistors,
a square wave should be good enough.
Power can be measured with a shottky diode RF detector and either a DVM
Nano analog input pin.
Would be nice to have a proven recipe for this.
Jerry, KE7ER
On Wed, Mar 6, 2019 at 10:35 PM, Ashhar Farhan wrote:
- the ubitx has more gain on tx as well as rx than the previous boards.
this is due to the BFR93w transistors in the 45 MHZ IF in place of the
2N3904s.?
- The carrier and spurs will be appear to be higher if the tx gain
(controlled by RV1) is running flat out. it is best to reduce this to
about 60% of the full gain. A way to know this is to connect a 50 mv
audio signal to the mic, transmit SSB on 7 MHz and reduce the power until
it is around 7 watts.
- ?
- - f
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Re: change keyer type on nextion
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Morning Dave. ?????????????????????? Thanks for the information on the mouse details,im at a loose end today so will delve into? my junk box as i now ive an old wired mouse there.Soory to hear about your wife,our 30 year old son is autistic and epileptic and lives with us 24/7 you cant trust the carers as we found out,we tried to sue them but a big organisation like that just hired a barristor and they got away with it.It took alot of our savings also.so now he is here with us and at least we know his life is being fulfilled and leading as normal a life as can be.Regards Dave G0AYD.Have a look at my qrz page
Dave Just take out the circuit board and cut through the traces around the two switches. Solder in two resistors and jumper the other end of the switches together. On mine I covered them with shrink tubing and there isn't much to see.
My wife in particular has severe Rheumatic and osteo arthritis. She wants to keep her fingers moving as long as possible. She has been holding the mouse in a conventional way. It has a built in palm rest.
Sorry to offend the Ditty Boppers. They have been doing things so long that they forget that there may be another way.? I was in the ASA back in 1970-73? 95 percent of the other soldiers in the unit were dittyboppers I was sent into electronic maintenance to fix what they broke or wore out. It never occurred to me that learning morse would be useful.
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Re: New V5 with poor carrier suppression.
IMHO, THE NAT54S ARE INTERALLY matched. As a strip, same batch the second bat54s also has similar characteristics.? Can we get such balance with 4 discrete diodes, it is a long exercise to match etc
On Fri, 8 Mar 2019, 8:19 am Tom, wb6b < wb6b@... wrote: Hi,
In theory shouldn't the mixer attached to CLK #0 be balanced and suppress the carrier? In that case the filters only need to suppress the unwanted sideband, not the carrier.
The matched mixer diodes are supposed to be matched well enough to not require a balance adjustment control pot. But has anyone tried adding a manual balance adjustment to these radios.
The mixer connected to CLK #2 could, also, cause an increased carrier if it was not in balance. As the on-purpose unbalancing of it to produce CW signals demonstrates.
Maybe a mixer diode in your radio is out of spec.?
Tom, wb6b
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I am using the mouse as a (ceramic) microphone for my Drake (the capsule fits perfectly in the place of the ball). Indeed I could use the two now unused buttons for a cw key as you have done hihi :) Might the squeeze function work with such a thing?
Il 08/mar/2019 07:31, "Curt via Groups.Io" <wb8yyy= [email protected]> ha scritto: Dave
Nice to see this idea revived as I know I saw it decades ago for portable operation.
Not everyone is doing 20 or 30 wpm and that is okay.
A bunch of us also do mechanical keying in straight key century club. The nice organization is quite a hoot. Some even use a sideways key called a cootie, many handmade.
Enjoy your radio.
Curt
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Maximum and minimum voltages for uBitX V5?
I'm building my uBitX v5 and have a couple of questions about power supply voltage.
?
First, what are the minimum and maximum supply voltages that the uBitX is happy with? ?I may be powering the radio with a 12AH AGM battery that's kept charged by a solar panel. ?I'll probably set low voltage cutoff for the solar controller at 11.8 or 11.9 volts under load (I've seen that listed as 2 amps when transmitting). ?The float voltage will be 13.6 to 13.8 and there might be monthly excursions of 14.2 to 14.4. ?Some specific longer life AGM batteries are spec'ed to have a regular duration equalization charge - DataSafe 12HX330FR, for example - and I see no harm in occasionally taking any AGM battery to its maximum rated voltage (cyclic versus float).
?
If the uBitX isn't happy with that range (the LM386 could be either a 12 or 18 volt chip as the schematic just has "LM386"), I can control the voltage delivered to the receive section with an XL6009 buck/boost converter (maximum input is 3 amps). ?The XL6009 can hold the voltage to 12.0 volts or whatever makes the radio happy ;-)
?
Second, what's the maximum safe voltage for the PA? ?I could use 2 XL6009's, with one set for the receiver and the other set to the PA's maximum safe voltage to squeeze a few more watts out of it. ?I plan to have a fan running on +5 for RX and +12 for TX so there's some degree of cooling between transmissions.
?
I've not been active on HF for a long time but did have some articles published back when I had antenna space. ?I'm supposed to be talking with a tree guy this week and I may soon have antenna space again ;-)
Published articles:
"Gilding the Lily", 73 Magazine, October 1980
"Converting the Sears 40 Channel SSB CB Rig to 10 Meters", Cover Article, CQ Magazine, November 1980
?
John
WB4HLZ
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Dave
Nice to see this idea revived as I know I saw it decades ago for portable operation.
Not everyone is doing 20 or 30 wpm and that is okay.
A bunch of us also do mechanical keying in straight key century club. The nice organization is quite a hoot. Some even use a sideways key called a cootie, many handmade.
Enjoy your radio.
Curt
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Re: AGC Pre-Oders are in and built!
Hi Tim
I have a v5, am happy to test. Send me the file to print and I'll take some photos.
Cheers
Ben
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On Thu, Mar 7, 2019 at 07:55 AM, d balfour wrote:
Have thought about adding a electet mic
I like this. Reminds me of an old Star Trek movie where a crew member from the future was trying to use a mouse. Tom, wb6b
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Re: cannot trust any version or any mod.
It is more sensitive bc of the different transistors it's using .?
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Raj vu2zap
Ted
Vic WA4THR