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Re: A modern AD or SI5351/570 for an old dial !
Should be possible to use the old HW7 mechanical dial to program an Si5351..
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I assume the rig has the usual variable cap in the VFO for tuning, 180 degrees of rotation. One possibility would be to replace the variable cap with a high quality linear potentiometer, watch the voltage from the pot with an ADC? ?Use that measured voltage to program an Si5351. After mechanically installing the pot, use the ADC to measure the voltage at the bottom of the dial? and at the top for each band, and associate those ADC values with the dial frequency at those positions? All points in between are linear on both the dial and on the pot, and so should map well enough.? A 10 bit ADC is just barely sufficient, 12 bits would be better. If the dial is not quite linear, the software could perform piecewise linear interpolation. The Bitx40 used a pot for tuning, read from an ADC, programming an Si5351.. So the code is pretty much already written. I suggest you start with Allards codebase, he takes a number of measures to avoid? noise from the pot which would otherwise cause small jumps in frequency. ? ?? Alternately, use an ADC and digital IO pins to measure the existing variable capacitor: ? ??/g/BITX20/message/52471 Jerry, KE7ER On Sun, Aug 19, 2018 at 02:05 PM, ajparent1/KB1GMX wrote: This has appeared in may places... |
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Re: Modular uBitx - "Ex: Harmonics"
Allison Oh well, it was worth asking. Randy, K7AGE On Sun, Aug 19, 2018 at 10:38 AM, ajparent1/KB1GMX <kb1gmx@...> wrote: Randy, |
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New Group Specifically for "Homebrew Test Equipment"
Hello A few days ago I mentioned an idea for starting a separate discussion group for home-brew ham radio test equipment.? The idea still seems interesting but I seem to be struggling with what to call the group.? It needs to be short enough to type in easily, and still definitive enough to not be confused with equipment for testing pigs or homemade beer,? Some possible options that come to mind:
My Linux NFS File Server has a Test Equipment directory that already has several ideas which could be used as a start for this new discussion group. I am sure that others have similar card files or computer files which would be interesting to the rest of us who like building our own test equipment.? This does raise questions about how to differentiate hardware test equipment projects from combination hardware and software based test equipment? On a slightly different direction........ In the past there have been a few complaints about the amount of software discussion here on the BITX20 forum.? That raises the question of possibly starting a separate discussion group specifically for software that is relative to BITX based equipment.? Again, if such a forum were established, what should it be called?
In the case of Homebrew Test Equipment and a possible new BITX-Software group we would need a couple of volunteer moderators for each group. We already have spawned an Antenna discussion group at which is working quite well.? The moderators are doing a good job and some interesting discussion has started. I can start new discussion groups, but it is possible that someone else could do the same.? The process involves logging into the "create a group" page and filling out the form.? The process is quite easy and straightforward. It will not hurt my feelings if you want to start one of the above groups, or another group.? If you have ever envisioned yourself as being the Lord and King of a discussion group...Go For It ! Arv? K7HKL _._ |
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Re: uBitX CW bandwith
Howard,
As a learning test bed and experimental platform its great.? I've had a lot of fun with it and it has lead to other projects.? I'm sill playing with the Raduino as I write. As a result a beat Atlas210X will get the ideas born with Raduino but in a old school 5 band (80/40/10/15/10) radio but with modern ideas like split dual VFO, and other tricks the Arduino/5351 combo can deliver.? That and a really nice power amp for QRP.? ReAtlas210 maybe.? It was a good radio that worked but that sample had a VFO that was really bad and someone hacked up the power amp.? As many might now its also modular inside with the three plug in boards. Allison |
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Re: Two-tone test
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On 20 Aug 2018, at 6:49 am, jim via Groups.Io <ab7vf@...> wrote:
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Re: Two-tone test
jim
On Sunday, August 19, 2018, 12:24:04 PM PDT, Kevin Rea <reakevinscott@...> wrote:
Hi Jim, how do you connect the ubittek to the oscilloscope?
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For two-tone test?? "ubitx">>>>dummy load>>>>Tektronix P6100 10:1 probe to hot end of dummy load QRP levels will not exceed scope limits (5 w ~ 40 V (p-p) Jim |
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Re: A modern AD or SI5351/570 for an old dial !
This has appeared in may places...
it would be a royal pain to get a mechanical dial to encode to feed a DDS or 5351/570. As other suggested a tiny oled display is a good way to go. One I've seen was pretty slick but much more effort was to place a larger matrix LCD (or oled) behind the existing slot and make a software moving dial display. Takes a bit of programming to paint the dial (curved with dots and numbers) and update it with a standard encoder. To do that in the HW7 would be a lot of work. Allison |
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Comport issues
Finally after many attempts I was able to load the ch341 driver. It shows up in device manager as Lpt and com 3. When I install my as card it shows up as D: when I try to upload from Nextion editor it tells me connection failed. Nextion is using com 3. Any help would be greatly appreciated. I have been struggling. KN4LPH thanks
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Re: uBITX new build, quiet audio
#ubitx
Jack Purdum
Check your ground connections and you might try throwing on a couple of caps on the power leads to see if the hum is reduced. If you have a 12V battery, try running it on that. If the hum is still there, that pretty much tells you the hum is coming from somewhere else. Jack, W8TEE
On Sunday, August 19, 2018, 12:53:31 PM EDT, Benjamin Von Handorf <von.handorf@...> wrote:
Apologies, I suspect this is a common question but my poor google-fu hasn't turned up anything other than a blown TDA2822, which I don't think is my issue. I just finished my ?BITX build (v3 board... arrived the week before v4 came out :) ) and my receive audio is very quiet, both through headphones and through an 8 ohm speaker.? Even with the volume turned up to 100% even reasonably strong clear signals are almost swamped by hum (which I believe is power supply related, I don't think that's anything to do with the ?BITX). I do get audio, so I believe the fundamental wiring is correct and the volume does modulate with the volume pot.? I'm running off a 12V wall wart (reads at 12.2), so the power is a little below 14.1 but I'm not looking at the TX side yet.? The front panel of my case is metal, with the volume pot, rotary encoder and all the 3.5mm jacks mounted in it but I've tried removing them from the metal plate and it didn't seem to change the behavior at all. This is my first real radio build, so while I get the high level concepts I don't know where to look for mistakes when things don't work right.? Can anyone provide any guidance on where to find my screw-ups? Thanks, -Ben |
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Re: A modern AD or SI5351/570 for an old dial !
Jack Purdum
Robert: Why would it be "much easier" with an OLED? Many color TFT displays work with I2C? and are actually cheaper. The coding is about the same. Jack, W8TEE
On Sunday, August 19, 2018, 3:54:05 PM EDT, Robert McClements <gm4cid@...> wrote:
Hi, An interesting concept, difficult part will be keeping the original dial if your intention is to maintain the original dial markings. It would be much easier if you were to consider using a small 0.91 inch OLED for your display,? google 0.91 inch OLED Display. There was a post earlier on her detailing how to derive quadrature outputs from the si5351 using an arduino. |
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Re: A modern AD or SI5351/570 for an old dial !
Robert McClements
Hi,
An interesting concept, difficult part will be keeping the original dial if your intention is to maintain the original dial markings. It would be much easier if you were to consider using a small 0.91 inch OLED for your display,? google 0.91 inch OLED Display. There was a post earlier on her detailing how to derive quadrature outputs from the si5351 using an arduino. |
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Re: uBitX CW bandwith - sidetone
Hi,
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I successfully transplanted a 50k pot harvested from an old transistor radio. With 50k turned all the way "down" the sidetone is comparable to incoming signals:) No more shattered eardrums. And now - on to the CEC software. 73, Bill KU8H On 08/19/2018 01:39 PM, RCBoatGuy via Groups.Io wrote:
I think a lot of the problem stems from the uBitx being perceived as a --
bark less - wag more |
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Re: uBITX new build, quiet audio
#ubitx
Arv,
I have this hooked up to a 20/40m trap dipole that has been performing OK on WSPR, so I believe the antenna is at least acceptable.? I did my RX checks on 20 and 40.?? I'll take a look at the antenna connection.? I used the keyed connection provided with the radio but I may have reversed it on the BNC connector side. Thanks for the pointers! -Ben KN4COI |
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