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Re: Loss of CW Side tone When load N8ME Firmware.uBITX V6
Hi Chuck,
Two things come up to me as to loss in sidetone: 1 - The N8ME configuration 2 - The Nano has a hardware issue To address problem 1, verify that CW is selected on the main page and that the Side Tone is set in the configuration menu. Problem 2 could occur if you swapped Nanos in changing the two software programs. NOTE: I am running the N8ME software with the VU3GAO mods available in the files section. 73 Evan AC9TU |
Loss of CW Side tone When load N8ME Firmware.uBITX V6
Just replaced the Arduino Board and Main Radio Board.
Figured I look in to the Firmware of N8ME try something different interface. I been doing CW so this was suppose to make the uBITX more CW worthy. But I lost my CW side tone. going from standard Firmware to N8me Firmware. Any ideas of what may have happened. I reloaded the original Firmware CW side tone is back. Chuck K3CWE |
Re: #sbitx - an ugprade kit is on the way
#sBitx
Mark Earnest
This is good timing, I just let the magic smoke out of #077 (accidental high swr I believe)
Burnt the large traces near C11 and C85, I'm assuming I can replace Q18 and Q19 and resolder those traces. Oddly my RPI never went off so I'm assuming (I'll verify) my U2 buck converter didn't fail.? |
Re: #sbitx - an ugprade kit is on the way
#sBitx
The shipment? delay was to refit the existing orders with the switching regulators. So, yes. The new orders also have the spare IRFZ24Ns anyway. - f On Wed, Sep 7, 2022 at 9:33 AM kc5kwz <jrbritton@...> wrote:
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Re: #sbitx - an ugprade kit is on the way
#sBitx
¿ªÔÆÌåÓýWill all new orders include those parts too? ('cause I almost have enough penny's saved to make an order)-------- Original message -------- From: Ashhar Farhan <farhanbox@...> Date: 9/6/22 9:00 PM (GMT-06:00) Subject: Re: [BITX20] #sbitx - an ugprade kit is on the way #sBitx It is not really an upgrade kit. It is more a replacment kit. It has a switching regulator as a replacement for the LM338 that heats up a lot. It also has spare IRFZ24Ns just in case. On Wed, Sep 7, 2022, 6:58 AM kc5kwz <jrbritton@...> wrote:
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Re: #sbitx - an ugprade kit is on the way
#sBitx
It is not really an upgrade kit. It is more a replacment kit. It has a switching regulator as a replacement for the LM338 that heats up a lot. It also has spare IRFZ24Ns just in case. On Wed, Sep 7, 2022, 6:58 AM kc5kwz <jrbritton@...> wrote:
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Re: #sbitx - an ugprade kit is on the way
#sBitx
¿ªÔÆÌåÓýWhats in the upgrade kit? On 9/6/2022 7:46 PM, Gerald Sherman
wrote:
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Re: #sbitx - an ugprade kit is on the way
#sBitx
¿ªÔÆÌåÓýI haven't seen mine in Winnipeg as of today (Sept. 6) for serial #64 Gerry Sherman Sent by the Thunderbird On 2022-09-03 01:27, Ashhar Farhan
wrote:
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Re: Sbitx manual
¿ªÔÆÌåÓýThey are tricky little critters! I had to put two in series for exactly that reason in a uninterruptible power supply/charger system that I designed.?On Sep 6, 2022, at 15:25, Max via groups.io <kg4pid@...> wrote:
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Re: Sbitx manual
Thanks Jerry, since I know nothing about these devices I had to ask. Max
On Tuesday, September 6, 2022, 12:05:13 PM CDT, Jerry Gaffke via groups.io <jgaffke@...> wrote:
You can't fully turn off the PFET in this application since the intrinsic body diode allows current to flow from the battery to the rig.? You could add a second PFET in series with this one? but this time have the source pin facing the battery, yank the gate down toward ground to turn it on but be careful to avoid exceeding the Vgs spec.. On Tue, Sep 6, 2022 at 06:58 AM, Max wrote:
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Re: Sbitx manual
You can't fully turn off the PFET in this application since the intrinsic body diode allows current to flow
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from the battery to the rig.? You could add a second PFET in series with this one? but this time have the source pin facing the battery, yank the gate down toward ground to turn it on but be careful to avoid exceeding the Vgs spec.. On Tue, Sep 6, 2022 at 06:58 AM, Max wrote:
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Re: Sbitx manual
The trick to searching on Mouser is to select large fields of values for the various parameters.
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For example, I selected all values of Rds that were 5 mOhms or less by holding the Control key down while dragging the mouse across the desired values. Here's the same search, but I have removed the requirement that the drain current be at least 50 Amps continuous: https://www.mouser.com/c/semiconductors/discrete-semiconductors/transistors/mosfet/?channel%20mode=Enhancement&rds%20on%20-%20drain-source%20resistance=1.25%20mOhms~~5%20mOhms&transistor%20polarity=P-Channel&instock=y&sort=rds%20on%20-%20drain-source%20resistance&rp=semiconductors%2Fdiscrete-semiconductors%2Ftransistors%2Fmosfet%7C~Rds%20On%20-%20Drain-Source%20Resistance We now see several PFET's in an old style SOIC8 package with no heat tab, easy to work with but they can't dissipate quite so much heat. The most interesting of these is Mouser?512-FDS6681Z, which has an Rds of 3.8 mOhms and a Vds of 30v,? they have 67000 in stock and another 123000 coming later this month. I'd tend to skip over the 20v Vds parts if it might be getting used around significant voltage transients, such as in an automobile.? Page 4 of the datasheet suggests a temperature rise of somewhere between 50 and 125 degrees C per Watt dissipated, depending on how big the copper land areas are near the part in the PC board design. A reasonable figure might be 10 Amps per part if you just solder it to a board, 20 Amps if you have a good strategy to get heat away from it. For more than 20 Amps, you need more than one part. At 10 Amps, that would be 10*10*0.0038 = 0.38 Watts of power dissipation, and a temperature rise of 125*0.38 = 47.5 degrees C assuming not much attention is given to heat dissipation in the PC board design. This being a simple PFET, the junction temperature is rated for a max of 150 C before it fails (though odds of failure are rather high if kept anywhere near 150 C for very long).? So ambient temperature (the temperature of the PC board near the part) should be kept to under 150C - 47.5C = 102.5 C.? So long as the part doesn't get so hot that it sizzles spit, we should be fine. These PFET's only protect against connecting a battery or power supply with reverse polarity. For protecting all but the high power parts of the circuitry against too high of a voltage, I like using a low dropout linear regulator such as the LM2940CT-12, good for up to 1 Amp. That particular part also protects against reverse polarity, the older LM7812 parts do not. Jerry, KE7ER On Tue, Sep 6, 2022 at 01:37 AM, Gordon Gibby wrote:
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Re: More Updates
#sBitx
#sbitx-k3ng
Bill, The code is already integrated. Bob, Goody and I are changing the plumbing a bit before we add more modes. FreeDV, js8call and FT4 are at the top of the list. I would also love to do NBFM and AM On Tue, Sep 6, 2022, 8:59 PM bill steffey NY9H <Ny9h@...> wrote: Has there been conversation or mention of FT4 inclusion into Sbitx. |
Re: More Updates
#sBitx
#sbitx-k3ng
bill steffey NY9H
Has there been conversation or mention of FT4 inclusion into Sbitx.
So much faster and probably cooler on the finals ..... bill NY9H |
Re: Sbitx manual
I'm curious if a switch could be added to this circuit to turn it on and off? Or better still, could it be controlled via 3.3v or 5v logic with a few extra parts? I need an electronic switch and the added protection sure would be nice. Add in a 1.5KE15A 15-volt
transient suppressor diode and a fuse and you have over voltage protection as well.? Max KG4PID
On Sunday, September 4, 2022, 04:45:54 PM CDT, Gordon Gibby <docvacuumtubes@...> wrote:
In our neck of the words, if a radio is important to us we build a polarity protector that connects directly to it. ?No battery or anything is allowed to connect direct again, must go through our polarity protector On Sep 4, 2022, at 17:24, otalado <s53c.lado@...> wrote:
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Re: Sbitx manual
¿ªÔÆÌåÓýOne of the simplest ONE component protection is a Polarized Relay. All the rigs I tinkered with in the 80-90s had a polarized relay on the TX final board. Raj On 06/09/2022 2:07 PM, Gordon Gibby
wrote:
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Re: Sbitx manual
That's FANTASTIC of you, Jerry.? ?Much slicker with the online stores than I had been.? ? I ordered 8 of the IPP80 version just to have a few more around the house since there are hundreds of them -- BUT THEY WONT LAST LONG FOLKS!! I also updated the Construction Manual with the availability information, giving the link to the available part.?? See:??? ?(now updated with a through-hole? part from your list)? Using the lowest possible Rds-on just makes this so so much easier on the builder.? ?The losses in our existing units through the MOSFETS are actually lower than through the crimped connectors etc in our powerpath.? ?I actually measured losses in fuses, fuse connectors etc that were larger than the losses in the MOSFETS!? ? That was very nice of you to do that search and point people to better choices! Thanks, Gordon Gibby KX4Z On Mon, Sep 5, 2022 at 9:31 PM Jerry Gaffke via <jgaffke=[email protected]> wrote:
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Re: DAYLIGHT ANALOG RADIO - 5MHZ WWV INTERFERENCE
Dave, Congratulations on the build! You can also move the IF to 4.915 MHz. It makes the frequency display a little more complicated but it is always a good idea to have an IF unlit by any of the standard frequencies. On Tue, Sep 6, 2022, 10:20 AM David R. Hassall WA5DJJ <dhassall@...> wrote:
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DAYLIGHT ANALOG RADIO - 5MHZ WWV INTERFERENCE
¿ªÔÆÌåÓýDear Members, I just finished wiring up my receiver modules and taking care of
this and that? when you first light of any home brew project.? Us
Amateurs on this side of the earth have the US National Bureau of
Standards Radio stations on 2.5MHz, 5MHz, 10MHz, and 20MHz
blasting out time and information signals 24/7.?? When I lit off
my DAYLIGHT ANALOG radio and was tuning around I had a beat note
in my receive audio.? Sure enough the 5MHz WWV time signals were
sneaking through my 7MHz Band Pass filter, through the first
mixer, crystal filter and beating against the BFO oscillators
signal in the 2nd Mixer.?? The Cure is simple.? A 5MHz trap made
from a T50-2 core with 32turns of #26 wire and put in series with
a 250pf of capacitance. (I used an old compression trimmer from my
junk box but the needed capacitance is somewhere between 220pf and
250pf to suck the 5MHz signal out.?? Now my DAYLIGHT ANALOG
receiver can listen to 40M SSB DX from Central and South America,
FT8 tones, and some really good clear CW.?? The only think to note
is that Experimental Methods in RF Design on page 5-12 recommends
that the PTO and the BFO signals be about 5V Pk to PK.? My PTO was
much lower than that and I have changed the 78L05 voltage
regulator to a 78L09 and my PTO signal is not quite 5V PK to PK
but the received signals have improved.? So, I believe that is
worthwhile doing. For those who are curious what the 5MHz trap looks like in reality, Here is a picture of mine.? (It is not the gold standard, but it did work very well) Keep at it.?? This radio is well worth the effort to collect all the parts and build it.?? It will teach you many things and not just the stuff that comes out of a book (but the book helps....hi hi) Take care and have fun.? 73 Dave WA5DJJ -- 73 Dave WA5DJJ SUPER GRABBER WEBSITE: EMAIL: dhassall@... |