Keyboard Shortcuts
ctrl + shift + ? :
Show all keyboard shortcuts
ctrl + g :
Navigate to a group
ctrl + shift + f :
Find
ctrl + / :
Quick actions
esc to dismiss
Likes
- BITX20
- Messages
Search
|
Re: Board Map/Layout, Test Points? (V5)
Gordon Gibby
¿ªÔÆÌåÓýIn the old Kenwood days, it was not likely that an amateur radio operator would be able to duplicate the boards. ? That¡¯s no longer the case.I¡¯ve had to figure out a few different connections in order to create the instructions on how to add an external daughter board to handle relay switches.
It wasn¡¯t that hard. ? So I think most of us can succeed to the degree we need. ? ?
I have now ordered the siglent spectrum analyzer, which apparently is on backorder until April 12. ? The point raised by some here that service is available in the United States for that brand, ?made the difference.?? I hope to have it by the beginning
of May, to help deal with a noise problem at the emergency operations center (EOC) ?in our county. ? ? I¡¯ve also managed to get a dummy load with a real RF 30 DB tap, possibly better than the homemade one that I made. ??
At some point I will then get the time to return to playing with these fascinating radios. ?Check my v3 with the outboard relay fix. ?? ?Get one of the new version fives, maybe put it in one of the nicer cases, see if adding one extra stage or so to some
of the output low pass filter¡¯s makes any difference. ? If the relay wiring has been cleaned up, or if the daughterboard idea I¡¯ve built is as successful as I thought, then one would think that adding even a little bit more would make it wildly successful.
? ?
I also need to widen out that crystal filter just a tad for WINLINK. ? And the same on a bitx 40 I have. ? ?I¡¯ve got a little transistor hundred watt amp that I need to assemble, and then I think it could be a really cool ALE ?or WINLINK gateway.?
Cheers
Gordon
|
|
Re: Reverse Polarity Protection.
Sorry to hear about your uBitx board.? I have used these testers:
with some success in circuit testing.? Since it is just looking for gain, it is a fairly good indication that the device is not dead.? Been a handy device as it can also check caps and coils, though not too small of values. The devices are available from a number of manufacturers on the Web. 73 Evan AC9TU |
|
Re: Board Map/Layout, Test Points? (V5)
Gordon Gibby
¿ªÔÆÌåÓýIn this day and age, that would be somewhat like demanding he give up corporate intelligence knowledge. ?Layout is a valuable commodity.
|
|
Re: Reverse Polarity Protection.
¿ªÔÆÌåÓýJust a warning to any hams selling batteries at swaps. Please don¡¯t put red price stickers next to the negative battery pole......Don¡¯t ask me why. I now check all batteries I might buy when I get home and mask off a big square around the positive pole and paint it bright red. ?Late at night and in haste my eyes and brain don¡¯t coordinate well. ?Enough smoke in the shack from my soldering. Dave K8WPE David J. Wilcox K8WPE¡¯s iPad On Mar 27, 2019, at 5:02 AM, Denys VK3zyz <dendad51@...> wrote:
|
|
Re: Reverse Polarity Protection.
Ah, thanks for that info Evan.
I'll upgrade the polyswitch. I have them from 50mA to 8Amps here in stock. Still, I've not got my board going correctly. It is distorted and deaf so I think a mixer is damaged. It is looking like removing the transistors one by one to test them.? Hot air tool and tweezers to work! |
|
Re: Reverse Polarity Protection.
Since it is 1 amp, I assume that it is only protecting the board, and not the PA.? When on 80 meters, my v4 and v5 boards will draw 2+ amps total.? That would be close to the trip point of the poly switch that you specified.
On my v5 rig, I have split the fuses, and have 2 1n4001 diodes in series from the 13.5 vdc supplying the rig and the separate feed to the board (red wire on the supplied connector).? The reverse protection is then on the fuse for the PA, since the two series diodes would protect the rest of the board from reverse power.? If i connect the power supply incorrectly, the 3 amp fuse in the PA lead will pop.? This arrangement also allows me to remove the PA fuse and power the rest of the transceiver for testing.? When doing this, the reverse protection is the diodes in series with the power supply to drop the voltage to just under 12 volts. 73 Evan AC9TU |
|
Re: Board Map/Layout, Test Points? (V5)
I don't remember, Farhan has ever released board? layout or its photo Sarma? ?vu3zmv On Tue, 26 Mar 2019, 10:49 pm ronmhauser via Groups.Io <ronmhauser=[email protected] wrote: New Question:? I have the high res PDF schematic, and I have been searching around to see if I can find a high resolution board layout or graphic.? Is this out on the web somewhere?? |
|
Re: Reverse Polarity Protection.
I would agree, as I too had a reverse polarity issue.? For me it was a left over HP power brick; HP has for some reason reverse polarity on the barrel connectors.? I forgot this and plugged it in.? Never got to turn on the rig, as the power supply crow bar shut down the power supply.? Would have fried the rig if I had not wired up the diode as listed in the wiring directions.? The only thing I would add is make sure you have a fuse in line upstream of the diode.? This is really critical if your supply can provide more than 3 amps, and does not have a crow bar shutdown circuit.
73 Evan AC9TU |
|
Re: Shaking my head in disbelief....
Kelly Mabry
?Well after a few hours of teardown and reassembly, I salvaged the encoder and the board. It tunes flaky, tends to jump around, very sensitive tune rate....I also was able to hear wwv on 5 mhz. It does not jump in and of menus.
I have my Carolina windom connected to the ubitx, and am hearing strong signals, but not many so I am encouraged only slightly.? Next step is to relax, and fix the volume control..tomorrow.? At least it works and sounds like a radio! 73, Kelly K5AID? |
|
Re: Second Nano @ i2c for spectrum, meters, CW-decode, etc
Hi, Mike.
Thanks for reaching out.? I'll check out that YouTube tutorial; it's possible that I've seen it though a silent demo doesn't always reach me. I want to know why we're doing one thing instead of another that seemed OK but wasn't. I'll look you up and give a ring Wed. afternoon or evening, hopefully. Tnx agn & 73. Ted K3RTA |
|
It sounds like a good idea would be to buy a spare Arduino to play with. I have a couple so I have a going one, and one to fool with.
That is, I could play around with it before I hooked my uBitx V5 power up backwards :( Now I'm just trying to get it fully going again. (It now has the reverse polarity installed!) |
|
Pat Anderson
Yes, already tried that. The Raduino unplugged powers up with the USB cord, no black squares, just a blank yellow display. I tried compiling and uploading the Blink example, and same result, the system messages say " programmer not responding." So, I am guessing there might be an issue with the bootloader on the Arduino, but this is pretty much beyond me at this point, and I don't want to try anything that might brick the Radiuino, assuming it is not already bricked. Pretty sure I did not do anything that might have bricked it. This all started when I had finished the assembly and on first power on got the black rectangles, which I found on the forum other people have had the black rectangles as well, and then I found on Arduino forums the same thing had occurred on Arduinos not used for radio. On those other forums, it seemed the consensus was that the bootloader was missing or corrupted. That is where things stand today. Don't really know if my bitx-40 assembly was good because without the Raduino I cannot tune it. On Tue, Mar 26, 2019 at 6:30 PM <dendad51@...> wrote: It sounds like the Arduino is blank or dead. Can you unplug the Arduino from the Raduino board and just load "Blink" to it to check ti is ok? |
|
Reverse Polarity Protection.
I recommend you do install reverse polarity protection.
My v5 board now has a 1.A polyswitch and a reverse diode. I wish it did earlier!! For some reason, I thought I'd put that mod on later, and of course, just after getting it fully calibrated, I plugged the 12V gell cell battery in the wrong way around :( I've replaced the burnt track feeding the power amp, Q15 and the 5V reg on the control board. It sort off works, but has lost sensitivity and clarity so I think a mixer is suspect. So far, I've not figured out what is wrong. So, put the reverse protection on FIRST!!!!! |
|
Re: Mic distortion
The 0.001 mfd bypass at the microphone cartridge was sort of standard way back in the early days of BITX.? It worked then, so should be something to try now. Arv _._ On Tue, Mar 26, 2019 at 4:41 PM Martin Potter <ve3oat@...> wrote: I wonder if an RF by-pass capacitor (disk 0.01 uF) at the mic connector would do the job.? Anyone tried that? |
|
Re: Mic distortion
Another question, what mic are you using?? A dynamic mic would need to be connected through an preamp or compressor and isolated from the electret bias voltage.
I found the stock mic to not have enough drive, so added an amplified mic, and verified that I was not over driving the rig. 73 Evan AC9TU |
|
Re: Mic distortion
Is the problem only with the amp connected?? How is the signal running "barefoot".
Since you have another receiver, I would load the uBitx without the amp into a dummy load and verify the signal with your Kenwood.? If that does not have the distortion, then would check the linearity of the amp or the SWR between the uBitx and the amp. I also had issues with distorted audio when I had a miss adjusted BFO.? Put the output right on one of the edges of the filter, causing high frequency cut off on one end, and excessive carrier on the other. I have read some posts where multiple pots with relays were used to adjust the drive setting based on band selection.? As long as you shielded the connections with appropriate RF cables, I would think that you could have a switch with a resistor/pot to change value of drive. Again, these are my experiences and ideas, yours may be different. 73 Evan AC9TU |
David Wilcox K8WPE
Ted
to navigate to use esc to dismiss