Re: consistent sbitx failures
Then the drawing looks like this with Sbitx_v2:  -- Gyula HA3HZ
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Re: Solder flux syringe & hot air rework
0.012" tin/lead rosin core.? Makes hand-soldering SMTs with a pencil iron easy!?
It will spoil you. You will use this for all of your soldering, and never use the coarse stuff again!?
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I use a 30 watt American Beauty pencil iron for SMT soldering, and use a light dimmer for temperature control.?
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Re: consistent sbitx failures
Steve
?? That is a plausible explanation for my case 1 where I was playing with the iambic keyer so there were many transitions.
--
73
??? Bob? KD8CGH
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Re: consistent sbitx failures
If you search for 1N5349B on the forum, you will find the message I posted with the photos of how I installed the Zener diodes.
BTW - good to see you back on the forum!
73; Steve, N3SB
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Re: consistent sbitx failures
Perfect! ?? Later this week I hope to do some more mods on my developers addition and I wanted to know what voltage zener to add.?
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On Jul 1, 2023, at 11:20, Steve Beckman <n3sb@...> wrote:
?Hi Gordon;
The IRFZ24N data sheet suggests that 4 - 6 Volts on the gates should be sufficient. The RF behavior of these devices is probably more complex.
In place of a detailed analysis - I've had no problems getting 40+ Watts out on the lower frequency bands.
73; Steve, N3SB
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Re: consistent sbitx failures
Hi Gordon;
The IRFZ24N data sheet suggests that 4 - 6 Volts on the gates should be sufficient. The RF behavior of these devices is probably more complex.
In place of a detailed analysis - I've had no problems getting 40+ Watts out on the lower frequency bands.
73; Steve, N3SB
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Re: consistent sbitx failures
Is 12 V enough? Do you think that¡¯s enough drive?
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On Jul 1, 2023, at 10:34, Steve Beckman <n3sb@...> wrote:
?Another way to take out the finals is to put too much voltage on the gates. I have occasionally seen some large, very low frequency spikes on the gates of the PA transistors when transitioning from transmit to receive, It could be caused when the bias current is being removed from the pre-driver and driver stages, resulting in a collapse of the magnetic field in the inter-stage transformers.
Awhile back I installed back-to-back 1N5349B 12 Volt 5 Watt Zener diodes from the gates to ground at the PA transistors Q16 and Q17.? Knock on wood - I've had no further PA transistor failures.
73; Steve, N3SB
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Re: sBitx v2 Signal strength display
The short answer, there is NO signal strength meter, yet. This is just one of many feature yet to be incorporated into the sBitx software. It will come soon.
Joel
N6ALT
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Re: consistent sbitx failures
Another way to take out the finals is to put too much voltage on the gates. I have occasionally seen some large, very low frequency spikes on the gates of the PA transistors when transitioning from transmit to receive, It could be caused when the bias current is being removed from the pre-driver and driver stages, resulting in a collapse of the magnetic field in the inter-stage transformers.
Awhile back I installed back-to-back 1N5349B 12 Volt 5 Watt Zener diodes from the gates to ground at the PA transistors Q16 and Q17.? Knock on wood - I've had no further PA transistor failures.
73; Steve, N3SB
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Re: sBitx v2 Signal strength display
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Re: The content of hw_settings.ini is incorrect
#sbitx_v2
ps.: I will correct it, because the type of diodes is not OA60, but 1N60.
I mistakenly wrote this on the holder, but I looked it up again.
I bought it back in January 2010.
--
Gyula HA3HZ
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Re: The content of hw_settings.ini is incorrect
#sbitx_v2
I replaced the Ge diodes D27 and D28 with OA1160 Tungsram (340mV) in my previous testing, which did not give the desired result.
I replaced the diodes with OA60, whose opening voltage is 165mV.
I changed the ini files back to default and the measurements showed that the power displayed on the screen is the same as the external power meter.
I checked user_settings.ini where bridge=100, so no need to calibrate the meter.
Output power varied only slightly in each band. I used to increase the scale value per bar, but that didn't help now.
Can anyone help me how to proceed?
--
Gyula HA3HZ
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Re: consistent sbitx failures
Allison ? Yes, it is a V2. #20. Previously I had failed the finals by trying to document the RF power rise with time. I assumed that that was my fault. /g/BITX20/message/102215Case two and three could be cases of very bad thermal runaway. I'm at a loss to see how it failed with the drive set to 1. Since the Pi knows the forward RF power and sets the drive it would be good if you set the required power and let the Pi manage the drive level. That way it could cut drive as the finals heated to help prevent runaway. Plus power out is what users really want to control. -- 73 ??? Bob? KD8CGH
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Hello everyone, thank you for your willingness to help me. I will follow the last suggestion restarting from CEC 1.2 source code With Memory Manager recalibrating the uBITX. I will also try the CEC V2.0 Beta with the Setting Editor.
I will let you know the results of the new tests.
Just a curiosity, instead of AVRDUDESS which sw do you use ?
Greetings.
?
73, of IK0XBC
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Re: SBITX V2 - DUAL MONITORS?
On Tue, Jun 27, 2023 at 05:16 PM, Scott KE8KYP wrote:
?sudo xinput map-to-output ¡°raspberrypi-stop¡± ¡°DSI-1¡±.
Scott, First, thank you for the information on dual monitor use with sbitx.?? On point in the above post: There is a typo in the mapping command.? it should be sudo xinput map-to-output ¡° raspberrypi-ts¡± ¡°DSI-1¡± 73 Evan AC9TU
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sBitx v2 Signal strength display
Hi all, I have looked everywhere but I can't seem to find the signal strength display to report to contacts. Am I looking in the wrong place or just missing something?
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Re: Solder flux syringe & hot air rework
I like this flux. Works well and has a nice tackiness to help hold components.
AMTECH NC-559-V2-TF no-clean tacky flux for hand-soldering Tin/Lead
------- Original Message -------
On Friday, June 30th, 2023 at 09:48, Tech Guy <tech48055@...> wrote:
I am looking for a basic hot air rework/ soldering station. My 30 year old Ungar iron is too big for surface mount. Any suggested brands of solder flux in a syringe? I have used ChipQuik in the past for some projects. Any low temp roll solder that works well?
73¡¯s John N4HNO?
hope this is not a double post-internet is very bad here today
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Solder flux syringe & hot air rework
I am looking for a basic hot air rework/ soldering station. My 30 year old Ungar iron is too big for surface mount. Any suggested brands of solder flux in a syringe? I have used ChipQuik in the past for some projects. Any low temp roll solder that works well?
73¡¯s John N4HNO?
hope this is not a double post-internet is very bad here today
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In my limited experience, the IC-7300 also works well at a small multi-transmitter station that uses external bandpass filters and that only puts one signal on each band. If you're in 2A or 3A that's generally not a problem. Where it fails is when you try to have two or three transmitters on the same band at the same time (CW, SSB, and/or digital), which you'll probably be doing once you get above three transmitters. (Especially during the low part of the sunspot cycle, which is not where we are now.)
The IC-7610 has a similar front end design, so it's likely to have the same problem. But I have no personal experience with it in that regard.
The Field Day station I was at this year (W1BOS, 3A) did put transmitters on 75 and 80 meters in the middle of the night. We had separate antennas for those, at right angles to minimize interaction. (A low 80 meter dipole isn't all that directional so we weren't very concerned about which direction they were pointing, and on those bands you're going to largely be working NVIS paths anyway.) We used a K3 and something in the Flex 6000 series (I never operated it so I didn't catch which model it was) and they were quite happy. (Both radios had bandpass filters, but those did nothing to same-band signals.) We did NOT attempt to use our IC-7610 for that, based on reports from others.
On Fri, Jun 30, 2023 at 11:07?AM Dave New, N8SBE < n8sbe@...> wrote:
Jim,
I 2nd Jack's reply.? I notice you said something about maybe doing a Field Day.
The IC-7300 would be a great Field Day radio, if you are the only transmitter at the site.
Otherwise, in multi-multi Field Days, our experience is that trying to use an IC-7300 is an exercise in frustration, because the direct-sampling receiver fronted in the IC-7300 is easily overloaded by nearby transmitters.? We even tried an IC-7610 this year at the GOTA station, and ended up subbing in my 'spare' Elecraft K3S, which preformed admirably.
If you hang out on the Elecraft mailing lists, you will find from time to time someone who is selling their K3 or K3S, because they recently upgraded to a K4 or K4D.? Depending on what options are installed, the resale price will vary considerably, but a stripped down? used 100W K3 with one or two roofing filters might go for about what you are thinking of.? An original 100W K3 with one roofing filter used to sell for $1950 new about fourteen years ago.? Elecraft gear keeps their resale value.
We also found out that not all direct-sampling receivers are alike, since my Elecraft K4D performed well.? The only noticeable issue was the Yaesu FTdx101d, when used on FT8 on 20M put out some composite phase noise that I was able to pick up on the K4D which was on 20M CW at the time.? It was enough to be noticeable on the waterfall display, but since we were running CW with a 400 Hz bandwidth, the additional noise was not really noticeable.? This was using multiband dipoles oriented end-to-end for minimal coupling for each station, and about 200 hundred feet apart.? All stations at our 4A with GOTA site were running 100W, and all the remaining stations were K3's with upgraded LO boards or K3S's.? Never heard a peep out of the other stations, unless you got within 15-20 kHz of each other.? We were using contest filters on all the stations, but they don't help at all with in-band issues, since they all cover a complete band, not just a portion of a given band.
73,
-- Dave, N8SBE
On 2023-06-28 15:16, Jack, W8TEE via wrote:
?
The IC-7300 is a very good radio and a wise choice as they are not too expensive for what you get. Gigaparts has them new for about $1100 and you can find them used for around $900. The fact they hold their resale value is a good sign of their worth!
?
Jack, W8TEE
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On Wednesday, June 28, 2023 at 12:54:35 PM EDT, Jim < winickyj@...> wrote: ?
?
It would be helpful if you could answer these questions:
??? 1. What mode(s) do you expect to use most (e.g., SSB, CW, digital)?
? ? ? ? ?Just starting in HF so voice,? I am interested in using digital modes and Maybe CW eventuall
??? 2. What power level to you want to use (e.g., QRP, 100W, or more)?
? ? ? ? ?No sure how much I need,? Not wanting to be limited to QRP but figure if I need nore in future I could get amp.? looking for all around starter rig.
??? 3. Will it be an "at home rig" only, or will you also want to do SOTA, POTA, and other off-site activations.
? ? ? ? ?Primarily at home for now,? but may want to do a field day at some point
??? 4. What kind of antenna would you like to deploy.
? ? ? ? ?Don't know something relatively simple to start like a DX Commander.? I have some roof spaceand some suburban yard space.
??? 5. What's your budget? (Disregard if you're not married.)
? ? ? ? ?I was thinking of a 7300 as a starter? radio
-- Jack, W8TEE
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Re: consistent sbitx failures
Bob and I both know it's V2.
--
Gyula HA3HZ
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HA3HZ
N0YWB
Bob Benedict, KD8CGH
Joel Caulkins/N6ALT
Bruce W4BRU
IK0XBC
Shirley Dulcey KE1L