Re: Fried irf510s replaced but
Thanks Conrad; Adrian and Tim.? Yep I can see the inline fuse is a must.? Was also thinking about a master heatsink so the warning about the heatsinks needing to be isolated from each other was timely.? will check Q90 and update this chain once I have done so. ?
cheers Jeff VK3GMO, ex WA2GMO
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Is the gain slider in wsjt-x in about the middle of its range? ?Does the radio do ok with ssb voice? ?
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Re: Fried irf510s replaced but
Check transistor Q90 . it is what I replaced last time I had the same problem.
73;
AB6ST - Conrad
On Thu, Aug 23, 2018 at 9:10 PM jfein2000 via Groups.Io <jfein2000= [email protected]> wrote: My uBITX was working for cw and ssb but the irf510s were running too hot.? All output dropped to zero, no smoke or dramas and I was sure the IRF510s were fried and I just happened to have four more around so replaced them.? No joy.? Changed them over suspecting one of them might have been defective.? With the new ones in the Ubitx powered up fine and I started the bias adjustment.? It was showing about 450 ma initially and I tried to bring it up the 100 ma over that, current draw shot up to over 5 amps and this time there was smoke.? The trace from the positive 12 volt on board 3 pin connector was burned and I jumped it, replaced the irf510s and tested them before putting them in.? The seemed to be switching ok.? I checked all the toroids for continuity and they look good. ? So now I can get the 450 ma and can adjust the bias up ok but I am getting no output.? If I plug in the key the power seems to short and there is a strange hissing noise.? None of the wiring has been altered since the unit was working and all connections look good.? Speaking into the mike doesn't budge the current draw as it should so I am thinking something else has burned out.? Any suggestions would be appreciated if anyone has experienced a similar event? Thanks Jeff
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We got wsjtx 1.9.1 installed on Linux and wanted to try FT8 on the uBITX (with CEC firmware 1.080).? Using the FT-817 setting, frequency selection and PTT work as expected.??Receive is fine but transmit is not quite right.? We?monitor using a separate SSB receiver without an antenna.? When wsjtx puts the uBITX into transmit, we hear a very loud carrier tone and just above it (much softer) we can hear the transmitted FT8 signal).? I'm surprised to hear the carrier.? Another odd thing is that my wattmeter shows 0 watts while transmitting (not even a wiggle).? We?get about 10W out when I key down on the straight key.?
Have any of you experienced uBITX/FT8 folks seen this before?? Thanks!
73 Mike KK7ER
(and son KI7ZZS)
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Re: Fried irf510s replaced but
as AW pointed out,? the Hsinks are not isolated from rail voltage.? In some cases because of the anodising and depending on the plating of the screw used to pull the IRF up to the heat sink,? they may in fact have some electrical isolation.? When you replace the IRFs that will/,may be disturbed. So if they heat sink had an accidental ground that was not SEEN by the cct and then you replace the IRF you may have established? a path from the Drain tab to ground.? Also a? Gotcha waiting for people who don't like the temperature the IRFs are seeing . Not only do the Hsinks need to be isolated from GND ; they need to be isolated one to the other. So any one trying to put in a Master Hsink to cover both needs to find mica washers,? insulating nylon grommets and heat sink paste to do the job.? ?This does not apply in case of the RDHH16 and 15 Mosfets because the pinning is different.?
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Re: Fried irf510s replaced but
The standard heat sink is to small. To make it worse there is no heat sink paste on them to transfer the heat to start with. ?those poor Fets ?get cooked. ?If you can¡¯t leave your fingers ?on them it¡¯s to hot. ?? Remember the 12volt rail is on them as well so have a inline fuse 3amps to protect your pcb.
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On 24 Aug 2018, at 11:40 am, jfein2000 via Groups.Io < jfein2000@...> wrote: My uBITX was working for cw and ssb but the irf510s were running too hot.? All output dropped to zero, no smoke or dramas and I was sure the IRF510s were fried and I just happened to have four more around so replaced them.? No joy.? Changed them over suspecting one of them might have been defective.? With the new ones in the Ubitx powered up fine and I started the bias adjustment.? It was showing about 450 ma initially and I tried to bring it up the 100 ma over that, current draw shot up to over 5 amps and this time there was smoke.? The trace from the positive 12 volt on board 3 pin connector was burned and I jumped it, replaced the irf510s and tested them before putting them in.? The seemed to be switching ok.? I checked all the toroids for continuity and they look good. ? So now I can get the 450 ma and can adjust the bias up ok but I am getting no output.? If I plug in the key the power seems to short and there is a strange hissing noise.? None of the wiring has been altered since the unit was working and all connections look good.? Speaking into the mike doesn't budge the current draw as it should so I am thinking something else has burned out.? Any suggestions would be appreciated if anyone has experienced a similar event? Thanks Jeff
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Fried irf510s replaced but
My uBITX was working for cw and ssb but the irf510s were running too hot.? All output dropped to zero, no smoke or dramas and I was sure the IRF510s were fried and I just happened to have four more around so replaced them.? No joy.? Changed them over suspecting one of them might have been defective.? With the new ones in the Ubitx powered up fine and I started the bias adjustment.? It was showing about 450 ma initially and I tried to bring it up the 100 ma over that, current draw shot up to over 5 amps and this time there was smoke.? The trace from the positive 12 volt on board 3 pin connector was burned and I jumped it, replaced the irf510s and tested them before putting them in.? The seemed to be switching ok.? I checked all the toroids for continuity and they look good. ? So now I can get the 450 ma and can adjust the bias up ok but I am getting no output.? If I plug in the key the power seems to short and there is a strange hissing noise.? None of the wiring has been altered since the unit was working and all connections look good.? Speaking into the mike doesn't budge the current draw as it should so I am thinking something else has burned out.? Any suggestions would be appreciated if anyone has experienced a similar event? Thanks Jeff
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Re: Nextion 3.2 for CEC 1.097
#ubitx
I've done some more tweaking for the 3.2"
Basic HMI
Enhanced HMI
Basic TFT
Enhanced TFT
Here's a video showing some of he screens
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Re: Nextion 3.2 for CEC 1.097
#ubitx
Yes, setting the screen for 3.5" in the editor will let you use it, it just won't be formatted for the higher resolution 3.5" screen.
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I damaged the Nano on the?Raduino board (bad wiring job on my side unfortunately). Is there any place to get a replacement Raduino board (I could solder in a new?NANO if need be, but would rather not have to do so?
Thanks.
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Re: uBITX new build, quiet audio
#ubitx
Thanks for all the feedback and suggestions.? I haven't had time to work through everything yet, but here is what I have learned:
- I get similar hum on a SLA battery.? The voltage is a bit low (it's an old, mostly dead battery) but it definitely sounds similar.
- I took a pass at getting better grounding around the board with no results.? More to do here.
- I checked the antenna connection.? The connector is keyed correctly, from what I can tell, with brown going to the signal trace on the board and black going to ground.? Brown is going to the center of my BNC.
- The audio is extremely quiet even on side tone when I key down into the dummy load.? Through the 8 ohm speaker or head phones with the audio gain all the way up, it is just barely a whisper volume.
- Key down into a dummy load @ 12.1V, I'm getting around 4 watts on 40m.? Not sure if this is relevant or not, but another data point.
I do have a small amplified speaker so I can certainly use that, but it sounds like my experience is at least somewhat different than most so I'm interested in pursuing the differences, more for the learning experience than anything else.
Hoping to have some time this weekend to follow up further and do some more measurements.
Thanks,
73 Ben KN4COI
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Re: Wow... 15 volts in and a bunch out..
Having a blast on 20, with a W4OP mag loop indoors.? 
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Re: Nextion 3.2 for CEC 1.097
#ubitx
Hi Darren, using your 3.2'' hmi file I compiled it to my 3.5'' with Nextion editor, and my display is now larger than before,as large as yours.
Thank you very much. But of course I expect somebody will do it for 3.5'' basic.
Alper TA2FU
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A couple of small notes:
1. Be sure to replace "User" with your windows user name in C:\Users\User\AppData\Local\Temp\arduino_build_692458/JackAlV050.ino.elf or you might have trouble finding your file.
2. You can replace the 'C:\Users\User' part with the environment variable %USERPROFILE%.? This is particularly helpful in .bat(batch) programs.
Brian
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I had the tx relay get stuck on my ubitx. I replaced it with a standard relay and got it working fine. Might be way simpler than trying to adapt another component.?
Got them off ebay from china in 2 weeks I think they were $7.80 for 10.?
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Re: New version of TFT Touchscreen based VFO-BFO for uBitx
Hi Kevin,
The VU2SPF solution uses the MCUfriend type low cost touch tft which plugs straight into the Mega 2650 rather than the serial Nextion display.
73
Bob GM4CID?
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Re: BITX QSO Afternoon/Evening, Sunday, August 26, 3PM & 7PM Local Time, 7277 kHz in North America, 7177 kHz elsewhere.
Perhaps a future schedule could include a CW/RTTY calling frequency so that Technician Class licensees can participate.
73 Mike KK7ER
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Re: New version of TFT Touchscreen based VFO-BFO for uBitx
hi,
Does this work with the Nextion Enhanced 3.2" screen ?
kevin rea
lancaster, calif.
k6rea
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BITX QSO Afternoon/Evening, Sunday, August 26, 3PM & 7PM Local Time, 7277 kHz in North America, 7177 kHz elsewhere.
BITX QSO Afternoon/Evening, Sunday, August 26, 3PM & 7PM Local Time, 7277 kHz in North America, 7177 kHz elsewhere.
Join us as we make contacts with our BitX-40s or uBitXs or anything else on 7.277 MHz in 40 meters!
This is a worldwide event for BitX40 (and other QRP)?stations starting at 3PM and 7pm in each time zone. To participate, call CQ BitX on Sunday, starting at?3PM and/or 7PM?your local time. The BitX QSO Night continues through the evening and conditions usually improve after sunset, so it is worthwhile to participate later in the evening.
Suggested Best Operating Practices:
Work at QRP power levels unless conditions require more power.
Call and listen for CQ BITX on the hour and every quarter hour.
It is helpful if you call CQ BITX with your callsign, name and location.?
Repeat your callsign a number of times during your CQ BITX and during QSO's.
Start a QSO by confirming the callsign, location, name and signal report of the other operator.
Say the callsign, name and location of the other operator so others can hear.
If the frequency is busy, avoid long conversations.
After your initial QSO is complete, ask if there are any other stations who would like to contact.
Report your QSO's, discuss propagation, noise, signal reports, audio reports, antenna type, etc. in this thread.
This is an undirected, scheduled event.? The BITX QSO Night relies on you to call CQ BITX to initiate contacts with other stations, so warm up that final and transmit a few calls on Sunday evening.? Talk to you then!
--
John - WA2FZW
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On Thu, Aug 23, 2018 at 12:34 PM, Arvo W0VRA wrote:
Is there an easy way to check the IRF510 transistors?
They are not shorted drain to gate.
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Darren VE3XLT
TA2FU
Brian Bowling
_Dave_ AD0B
Arvo W0VRA