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Re: Noob tx problem
#ubitx-help
Just checked the mic at the plug.? It shows no continuity until I push the the button...then about 1.6k when I push the button. Have I wired the mic correctly?
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Re: Noob tx problem
#ubitx-help
Thanks for your help.? So I just checked with mic plugged in.? It seems to be shorting the ptt (orange wire) to ground without pushing the button.? Indicating a problem with the mic itself?
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Re: RF power chain mods and improvements..
I guess i don't understand where you are going with the software... but wouldn't it be easier to convert your display work from the I2C buss? ?Then you have a whole host of pins to work with... freed up from the parallel data lines of the ex-display?
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? Dr.?William J. Schmidt - K9HZ On Jun 6, 2018, at 11:42 PM, ajparent1/KB1GMX <kb1gmx@...> wrote:
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Re: Noob tx problem
#ubitx-help
¿ªÔÆÌåÓýDid you check with an ohmeter with the
unit off at the connector with the mic plugged in that the PTT
switch is working and wired to the right pin, i.e. high impedance
when not pushed, and short to ground when PTT is pushed?
On 6/6/2018 9:05 PM, davedt1e@... wrote: Still no joy.? I've checked all the wiring and confirmed connections to jacks with meter.? I wired up the mic and ptt button as a simple open/close circuit.? Is this correct?? Pretty frustrated.? Goes straight to tx when mic is plugged in.? Also verified that ptt button is working and soldering to the mic element looks good.
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ubitx & case
#ubitx
Bo Barry
My friend gave up despite all the help I gave so here's his equipment.
I have an unopened uBitx kit (I think version 3) and one of Sunil's cases (grey) plus parts also unopened.? Too many hardware and software changes for me to deal with.? $187.00 plus shipping, PayPal preferred but cleared check accepted.?? ?
Tim k5oi
Las Cruces, NM
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Re: Noob tx problem
#ubitx-help
Still no joy.? I've checked all the wiring and confirmed connections to jacks with meter.? I wired up the mic and ptt button as a simple open/close circuit.? Is this correct?? Pretty frustrated.? Goes straight to tx when mic is plugged in.? Also verified that ptt button is working and soldering to the mic element looks good.
Would appreciate any help.? Thanks |
Re: #bitx40 - CW Side Tone Wiring
#bitx40
Allard :?
You raise a good point.? By using R111 as the injection point for the constant +12V supply to the LM386, I avoid messing with the switching of the power to Q16. So Q16 is off during TX. The one thing that I did forget is that I actually have an "anti-thump mod" in place that grounds the input to the LM386 via a 2N7000 on PTT closure (see MSG # 25870). So this combination would explain why I don't hear audio from the mic in the headphones. ?It would be interesting for someone to try this mod on a BITX40?without an anti-thump mod in place to see if their is any appreciable mic audio getting through.? ?The danger when using a speaker on SSB ?is that you might get some audio feedback, which would be bad.? Cheers Michael VE3WMB? |
Re: HarleyHeat1ASCH
¿ªÔÆÌåÓýWell, it is a Heater
Control.? Done with a Pic and Assembly done code.? Lots of
nice features. I have not had a paycheck in 3 yrs now, so this design was part of a proposal. This is the nth
change, I keeps going on and on? A shot in the dark! Mike, WA6ISP On 6/6/2018 4:54 PM, William R Maxwell
wrote:
-- Mike Hagen, WA6ISP 10917 Bryant Street Yucaipa, Ca. 92399 (909) 918-0058 PayPal ID "MotDog@..." Mike@... |
Re: Mods and improvements..
If you are like me, Kent, nothing ever works right the first time. ?So, the answer to the last question is probably "no."?
I suggest building the radio into a temporary housing like a cardboard box and trying it out. ?You can always transfer it to a better cabinet and make a better informed set of mods easier in the process. Should you build it? ?Only you will ever know. ?I'm certainly happy with my results and what I learned in the process. 73, Tom ?W1EAT ? |
Re: HarleyHeat1ASCH
¿ªÔÆÌåÓýBut now you really should tell us what is, Mike.You have us all curious. Bill VK7MX
On 7/06/2018 9:30 AM, Michael Hagen
wrote:
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Re: Mods and improvements..
On Wed, Jun 6, 2018 at 04:15 pm, Doug W wrote:
I am running a totally stock rigI need to correct that.? I am running a totally stock board.? I have changed the audio pot to fit a knob I wanted to use and have added a fan to cool the irf510's even though Ashhar, the ?BIT's designer, doesn't think it is necessary as well as changing the LCD for a white on black one and using a non stock mic/ptt jack.? If anything my haste in responding and the other responses pilling up show you how many of us are very happy with this radio.? Build it, you will like it. ? -- |
Re: HarleyHeat1ASCH
¿ªÔÆÌåÓýA mistake, sorry.? Went to group when I meant to send it to myself. Mike, WA6ISP On 6/6/2018 3:18 PM, Allen Merrell via
Groups.Io wrote:
I am lost here, what is this. -- Mike Hagen, WA6ISP 10917 Bryant Street Yucaipa, Ca. 92399 (909) 918-0058 PayPal ID "MotDog@..." Mike@... |
Re: Mods and improvements..
Kent??? KQ4KK The mods and changes will never stop.? That is part of the BITX phenomena.? The transceivers are designed to be tinkered with, but basic units also work fine for those who do not want to tinker with the design or add modifications to make it fit their particular interests and desires.? Arv? K7HKL _._ On Wed, Jun 6, 2018 at 4:54 PM KENT HUFFORD <khufford@...> wrote:
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Re: Mods and improvements..
Seems to me the time to decide if you should shoot it before you pull the trigger.
IMNSHO for a little over $100 it is a steal.? I am running a totally stock rig.? It is the first ?BITX version sold.? Lately I have been operating mostly digital.? In just over a month I have hundreds of QSO's, I have worked all continents except for Antarctica, I am one state short of WAS and have many 1000 mile plus per watt contacts.? So will it work?? I tend to think so.? Don't let all the mods and improvements scare you off.? This is a very active community with many interests.? Build it stock to start and I bet you are happy. -- |
Re: uBitx on its way!
On Wed, Jun 6, 2018 at 06:37 am, Gwen Patton wrote:
I haven't put much effort into marketing but there is an option other than the guy on ebay for panels?/g/BITX20/message/50308 .? I went with a much more minimalist design approach.? Of course if you are like most of us you are going to want to make changes after your first build and will end up cutting, drilling and melting anyway.? Also while shielding the case is certainly a best practice many have gotten away without doing it.? I am not recommending (or admitting to) one way or another. ? -- |
Re: RF power chain mods and improvements..
One of the factors not reported was the consistency of the gain vs spur. Simple put
the gain and the spur interacted even when I held the level to the mixer constant. I'd lower the gain and the spur would get worse as an example.???It varied? greatly with supply voltage as well. Reason sluggish 3904s (low FT, Maybe Low? HFE).? Remember we are using a 300mhz device and that is a typical value and can be as low as 250 (batch and vendor) or much higher.? I changed them out for BFR106 (Q20, Q21, Q22), Seems the 3904s were not up to the task of keeping the amp load independent.? The net result was what others had reported as lower spur production, in mine it dropped the 10M spur nearly 12db.? So it was either distortion in the? 45Mhz amp or its ability to be a low output impedance which should be with emitter follower with the 47ohm making it look near 50 ohms.? I didn't? try 2n2963A as I didn't have any left in SMT but I suspect they would have been better. For now I'm taking a break on output power and addressing other things.? The power thing stands at 10W at 80m, 7W at 10M with the spur 46db down.?? I'll list all the changes as my unit stands while I do pop/click and mod then agc. For now mods I have in place, I'm not 100% happy but that is what us experimenters enjoy.? Likely others to come. ;) ? Replace and reset bias OF Q90 with 2n2369A or better (BFR106), Set bias for 18ma (r86 2.2K).? Make C81 470pf, and r83 8.2ohms. Change C82 to 470pf (peaking for 10M).?? T9 is now 9 turns #28 bifilar (one winding was never used). All the 2n3904s in the predriver and driver replaced with 2n2222A or better. Hint I mounted them on the underside with very short leads as it makes the top less crowded.?? Driver amp has 2.7uh SMT choke in series with R86 and that is now 1.6Kohms R87, r88 Both have a 270PF cap in parallel with them. R911,r96, R941, R942 emitter resistors for driver reduced to 11ohms (add parallel 22ohm). R92, R95 replaced with 1.5K ohm in series with 2.7uh choke.? (resets bias and adds peaking.) T10 has one less turn. T11 reduced by 1 turn. 45mhz IF replace (Q20, Q21, Q22) with BFR106.? Change R23 to 18ohms.? Change R27 to 39 ohms. !2mhz IF amp change R43 to 18 ohma and put a .1uf in series with 680 ohms across R41. Replaced Q10 with BFR106 for better receive gain at 20mhz and up.? (I may change out the two 3409s). Add LM7806 regulator in handy location to limit voltage to ta2822 to 6V on pin 2. Add 1K resistor from negative side of C77 to ground (prevents pop when pluging in headphone or speaker) Add 16K resistor from base o ground of Q70 for better overload performance. The one change that really helped the transmitter was going to the 2n2222A (TO18) part. Before that it was 13W on 80 and barely 7 on 40 and less on 20.? After that change alone 40 was near 10W and 20 was about 8.5W.? This has been tried on another unit that was weak on 40M and it really helped with no other tricks. Enough for now.? I plan to spend a few days re-rolling the software off the V4.3 release for my user interface which will not include CAT, CW or a rotary encoder.? Without CW mode the sidetone CW-Tone and CW-KEY pins are usable for general IO by removing R256 and R105. Allison |
Re: #bitx40 - CW Side Tone Wiring
#bitx40
Interesting Michael!
That seems to be a simple and effective mod! What surprises me though is: P.S. There are no undesirable side-effects (i.e. I don't hear audio from the mic in the headphones on SSB TX).The schematic suggests that the mic signal?will be?fed back to the audio amp during TX, so I'd expect you'd hear your own voice through the speaker while transmitting SSB. 73 Allard PE1NWL |