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Re: CW PTT attack time to slow
#ubitx
¿ªÔÆÌåÓýAllison: ? Thank you for the clarification. One last question, then, under firmware 1.095, can I use a single input for both straight-key an keyer mode? ? David A Posthuma, WD8PUO 1 (616) 283-7703 ? From: [email protected] <[email protected]> On Behalf Of W2CTX
Sent: Friday, August 31, 2018 10:10 PM To: [email protected] Subject: Re: [BITX20] CW PTT attack time to slow #ubitx ? On w0eb.com webpage is NANO software that implements interrupt driven CW generation.? Also eliminates the voltage divider scheme.? Also eliminates the need to switch between straight key and paddle as both are always active. ? rOn ?
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Re: uBitx Unfiltered
Gordon Gibby
¿ªÔÆÌåÓýWell, it was a kit.We all knew it was a kit. ??
I thought it might¡¯ve been a better kit, but as it was, it taught me a ton about RF amplifiers, ?about filters, about mixers, and about circuitboard RF design. ??
I bet I¡¯ve gotten $600 worth of education out of it.
That was way more than I was expecting when I bought it! ? I added about $12 worth of circuit board, relays etc., and I¡¯ve got a rig that will work 80/40/30/20 pretty good. ?Next on the list is one of those fancy transistors that I bought when Allyson
mentioned them. ?I will change out Q 90 and see what kind of power I can get then. ?Change an emitter capacitor and make it a little more flat. ?At that point it may do everything I want out of it. ?If not, I¡¯ve got a bunch of 2N2222 A¡¯s to work on the driver
stage. ? Put a wooden box around it, and call it done! ? I¡¯ve still put many less hours into it than I put into my Heathkit HW 16. ? And in 1971 I think I paid just about the same number of dollars that I had to pay for this incredible little learning tool.
? Adjusted for inflation, it¡¯s like I stole it.
If they ever find out how much good it did people like me, I hope they are magnanimous enough not to send me the bill!?
Cheers,
Gordon
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Re: uBitx Unfiltered
¿ªÔÆÌåÓýKees, ? Thank you for the reassurance. ? David A Posthuma, WD8PUO 1 (616) 283-7703 ? From: [email protected] <[email protected]> On Behalf Of Kees T ? David, |
Re: 4.2¡± Nextion Bezel?
¿ªÔÆÌåÓýChris: ? I greatly appreciated your offer to 3-D print. I just didn¡¯t want to put you through the trouble of having to order special materials you don¡¯t normally carry. I¡¯m sure I am not alone in wanting a bezel solution. So, if the group is aware that you have a solution, I think you would be of great service. Is there any place on the forum where people who offer various support-services such as this, can be easily found? ? Thanks, ? David A Posthuma, WD8PUO 1 (616) 283-7703 ? From: [email protected] <[email protected]> On Behalf Of Christopher Miller ? He is getting a laser cut acrylic version. I offered to print a few if he provided the material to produce the object . Instead they went with laser cut acrylic.? |
Re: uBitx Unfiltered
¿ªÔÆÌåÓýJerry: ? If it did come down to requiring a version-5 ubitx, I would hope there would be some discount to those of us who purchased version 3 or 4 with the understanding that it was a 80-10 meter transceiver, not just a legal 20-meter SSB transceiver with general coverage receive from 80-10 meters. I still hope a reasonable solution can be found to salvage the current generation of uBitx transceivers. ? David A Posthuma, WD8PUO 1 (616) 283-7703 ? From: [email protected] <[email protected]> On Behalf Of Jerry Gaffke via Groups.Io ? Of course, the uBitx should be a clean and solid 80-10m 10W rig.
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Re: uBitx Unfiltered
Jerry,
I was talking about an add-on filter board between T11 and K3 with all the existing onboard parts removed to populate the new plug-in filters or just disabled. Dual relay means a relay at each end of the LPFs/BPFs the filter is either connected to the RF bus or grounded, maximum number of series contacts is 2 and they are DPDT and bifurcated. Input RF and output RF is never combined in one relay, different LPFs/BPFs are never combined in one relay. 73 Kees K5BCQ |
Re: uBitx Unfiltered
Of course, the uBitx should be a clean and solid 80-10m 10W rig.
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Unfortunately, v3 and v4 don't quite do that, and would require extensive mods to achieve it. The high bands in particular are difficult. Perhaps v5 will come closer to the ideal. Jerry On Sat, Sep 1, 2018 at 09:59 AM, David Posthuma wrote:
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Re: KARMA and BITX
Way off topic.? The BITX20 group is not for politics. On Sat, Sep 1, 2018 at 10:59 AM Buddy Brannan <buddy@...> wrote:
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Re: KARMA and BITX
¿ªÔÆÌåÓýIsn¡¯t this like¡their third CEO in as many years (or perhaps two years)? Barry Shelley didn¡¯t last too long, did he? What¡¯s going on over there in Newington anyway?! I mean, apart from electronic magazines that are impossible to read with screen reading software.?
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Re: uBitx Unfiltered
¿ªÔÆÌåÓýKees & Team: ? I know my opinion may matter little since I am not an engineer but only a Ham for 44 years. I still have and use projects I built many decades ago. And when the sunspot cycle once again peaks, many of us who are now investing into perfecting our uBitx projects will regret if 15, 12, and 10 meters are not included in the final solution.? I want to encourage your team to think long-term and so strive for the most-excellent solution possible, that we all might be proud of our radios and enjoy them for many decades to come. ? ? David A Posthuma, WD8PUO 1 (616) 283-7703 ? From: [email protected] <[email protected]> On Behalf Of Jerry Gaffke via Groups.Io ? Kee's
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Re: uBitx Unfiltered
Kee's
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Are you talking filters at the output of the rig, for use with current v3 and v4 boards? That's likely the best bet for getting current rigs compliant. Me, I'm ok with dropping the high bands, maybe stick with just 80,40,20m. Killing spurs at 15m and 12m is difficult, and perhaps not worth the trouble at our latitudes given where we're at in the sunspot cycle. The current four transmit LPF's are sufficient for harmonic suppression if the board routing and relay scheme is clean. Not sure what a "basic dual relay" scheme is. I think the relay scheme of post 58293 is sufficient. Regarding where this rig should go on v5: Allison has said repeatedly that we need band specific band-pass filters where we currently have one 30mhz LPF at L1,2,3,4. She's built lots of this stuff and I respect her opinion. That's how pretty much all reg-compliant radios are built. But I am still very curious if we can tame the objectionable spurs with these changes: 1)? ?Use a PX1002 86.85mhz SAW filter instead of the 45mhz crystal filter (and appropriate transistors and transformers) 2)? ?Bring the local oscillators up to the required 7dBm.going into the mixers, keep mixer input signal levels 10dB below that 3)? ?Avoid having stuff from the power amp get into the IF amps. If that is sufficient to bring the spurs into compliance, we keep the radio almost as simple as it is now. The primary added complexity is additional gain required in the power amp to deal with the reduced signal from the mixers.? Somewhat related:? Clean up layout so the BFO does not jump across the 12mhz filter. Jerry,? KE7ER On Sat, Sep 1, 2018 at 09:20 AM, Kees T wrote:
Since most keep talking about the need for BPFs for certain bands, I "guess" the 80m-10m uBITX direction should be a board with 6 filter capability. How about a?basic?dual relay?switched filter board (3-1/4" x 3-7/8") with?up to?6 pluggable filters, all?manually?selected with a 6 position rotary switch --AND-- you can add a small mux board with 2N3904 relay drivers for the filters and a CD4028B mux to go from the 3 Raduino pins to the filters. Start with the existing 111,110,100,000 and add two others when you have the code modified. |
Re: CW PTT attack time to slow
#ubitx
Joop Stakenborg
¿ªÔÆÌåÓý
Okay! Sounds good, will have a look. I¡¯m afraid the stock firmware is unusable for serious CW transmissions. Thanks, Joop PG4I
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Re: CW PTT attack time to slow
#ubitx
Joop Stakenborg
Op 1 sep. 2018, om 03:41 heeft ajparent1/KB1GMX <kb1gmx@...> het volgende geschreven:Thanks Allison, I have now tried both the recent V4.3 from GitHub and KD8CEC¡¯s version. Ian¡¯s version works a bit better, attack time is improved but I am still missing part of the first dit to dah. The biggest issue is the software is a big loop and CW ke is checkedThanks for responding Regards Joop |
Re: uBitx Unfiltered
Makes more sense in this thread.............
Since most keep talking about the need for BPFs for certain bands, I "guess" the 80m-10m uBITX direction should be a board with 6 filter capability. How about a?basic?dual relay?switched filter board (3-1/4" x 3-7/8") with?up to?6 pluggable filters, all?manually?selected with a 6 position rotary switch --AND-- you can add a small mux board with 2N3904 relay drivers for the filters and a CD4028B mux to go from the 3 Raduino pins to the filters. Start with the existing 111,110,100,000 and add two others when you have the code modified. 73 Kees K5BCQ? |
Re: KARMA and BITX
Lawrence Macionski
Answer. The comment means- apparently someone is successful in the realm of electronics and ham radio. Another coincidental BITX success? It is simply newsworthy and I wish him well. Just like when Ashhar Farhan was inducted into CQ Amateur Radio Hall of Fame and noted here as well. Both men deserving.
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Re: Which xmit transistor is blown?
Sean,
Its been several days since you posted likely its eben seens and everyone is going "I dunno". ? ?Not enough description of whats going on or not going on. ? ?Not sure of the mods done. ? ?Are you sure the power supply is working ok. Everyone running FT8? without big fans seems to fry the amp and yet people run FT8 and likely at max power possible.? ?While technically it ignoring spurs and harmonics can there is insufficient cooling for sustained long transmit sessions.? HINT: cooling required. FYI hot is how hot?? You get a blister?? You don't what to hold your finger there long?? You feel warmth but its not painful? Many of the devices will heat to the very warm (about 140-150F).? That is not deadly to the devices.? It will make things like bad soldering stand out and maybe other marginal components fail.? Some have noted board level issues like open vias. Allison ? |
Re: UBITX V3 TX GAIN VARIATIONS
Jerry KE7ER,
>>I'll be buying that amp, once Hans starts selling it..?Then cut off the back half of my uBitx with a hacksaw. And you have half a radio....? That amp expect about 12-14dbm drive from the radio its attached to. That means for ubitx you still need about 32-34 db of gain hopefully not 3904s from the mixer output to the amp...? and still need a band pass filters for the bands above 17M and low pass filters, and there are issues with ground loops in the modulator and IF area. Its total gain is about 26-28DB.? To get from the mixer output though filters and result in 10W you need about 60DB of gain.? ? If you want even performance 3-30mhz you need to design that predriver section to be flat.? ? Which by the way is half the reason why the current amp has low power at 10M. As to the comment > Bag, cat, QSX amp.? The cats out of the bag, and its a QSX amp. Allison |