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LED for XMIT indication
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Hi, Looking at the schematic looks like an easy place to add a LED would be across the relay coil. Along with a current limiting resistor in series with the LED. Randy, K7AGE On Tue, Jan 3, 2017 at 3:23 PM, k1kob@... [BITX20] <BITX20@...> wrote:
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How many volts are going through there? Radio Shack sells 12V red colored LED's with a resistor built into them (I use one on the heated build platform of my homebrewed 3D printer, so I know when the bed has current running through it). Rich KC8MWG On Tuesday, January 3, 2017 7:23 PM, "Randy Hall listk7age@... [BITX20]" wrote:
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Ronny Julian
Randy what value would you say is god for a standard 5mm red LED? Ronny K4RJJ On Tue, Jan 3, 2017 at 7:23 PM, Randy Hall listk7age@... [BITX20] <BITX20@...> wrote:
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Hi There is 12 VDC across the coil when the PTT switch is pressed, closing the relay coil to GND. A 12 V LED, which would have an internal current limiting resistor, can be connected directly across the relay. A LED without an internal resistor will need a current limiting resistor. If the LED has a forward voltage drop of 1.7 volts. That would leave 12-1.7=10.3 volts across the resistor. Let's call it 10 volts to make it easy. And if we want about 15 mA for the current through both the LED and resistor, the resistor value is. R=V/I ?10/0.015=666 ohms. 680 ohm is a common value. Anything within 200 ohms will probably work.? Experiment with a LED and resistor across the 12 V power supply to see what works for you. Have fun Randy, K7AGE On Tue, Jan 3, 2017 at 4:39 PM, Ronny Julian k4rjjradio@... [BITX20] <BITX20@...> wrote:
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开云体育Ronny, Most red LED's have a forward voltage of about 1.65v, so at 12V that would be anywhere between 1K to 1.2K series resistor for about 11ma current flow through the LED. If you want it brighter you could drop that value to 800-900 ohms for about 20-25ma. I wouldn't go much lower or you'll toast your ?LED. Joel? KB6QVI On Jan 3, 2017, at 4:39 PM, Ronny Julian k4rjjradio@... [BITX20] <BITX20@...> wrote:
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Here's what I did - I tapped the TX / RX +12 points from the relay closest to the Power Connector.
This will give you +12 on RX, then on PTT, RX goes to zero (or nearly) and TX goes +12. This way, you can use a Red / Green Bi-Color LED. Green for 'ON / RX' Red for 'PTT / TX' In fact, there's a convenient spot near that relay, toward the corner, where you can glue or hot-glue a 3-pin connector (just like the ones on-board), but flush with the bottom of the PCB. Now you have a convenient plug-in point for your Red/Green LED. Since both LEDs won't be on at the same time, they can share a single current limiting resistor in the 'common' or 'ground' leg of the connector headed out to the Bi-Color LED. I think current draw for Red and Green are slightly different, but I just picked a resistor which would give me the most even light from each. Current draw is probably under 10 ma. for these LEDs, but it is a nice feature. You can tell if PTT is working. Mike Yancey, KM5Z Dallas, Texas |
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Well, I'm not sure photos would do, and it might take several. Plus there's 20 minutes of disassembly?
and re-assembly - it's screwed to the box...! However if you look at the schematic - lower left:? ... you'll see the PTT and the 'main' relay - Pins 1 and 3 are RX+12V and TX+12V, respectively. They're even LABELLED on the schematic as RX and TX! They're not labelled on the PCB, but you can even test this with a voltmeter. Pin 1 will be +12 during receive. PTT and it will drop and TX (Pin 3) will pop up to +12. Pick off your 'GREEN' and 'RED' anodes. Most Bicolor LEDs I've seen have a common cathode, so that (center) wire is ground.? You can pick up GROUND from this same relay - Pin 16 of the relay is ground.? ?? The PTT Relay is right in front (and down a bit) from the PTT connector. PIN 1 is 'down' & 'right' (if you're looking at the wireup.html page).
socket) Pin 16 is ground. You can either run it to a connector and 'crazy glue' or hot-glue to the PCB just underneath (and to the right of) the power connector - or, you can just run them in the free-air, maybe use some shrink tubing to keep them together. Just run them to your Bicolor LED. Mike Y |
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开云体育Hi , You may see the attached foto , zoom in to see the red & green wires soldered to the DIP relay points Green for Rx and Red for Tx which is fed to the dual color LED ( three terminal type) the centre goes thru a 680 ohms resisitor to gnd. happy homebrewing best 73 Pop VU2POP ? From: BITX20@... [mailto:BITX20@...]
Sent: Thursday, January 05, 2017 8:49 AM To: BITX20@... Subject: [BITX20] Re: LED for XMIT indication ? ? Well, I'm not sure photos would do, and it might take several. Plus there's 20 minutes of disassembly? and re-assembly - it's screwed to the box...! ... you'll see the PTT and the 'main' relay - Pins 1 and 3 are RX+12V and TX+12V, respectively. can even test this with a voltmeter. Pin 1 will be +12 during receive. PTT and it will drop and TX (Pin 3) will pop up to +12. ? Pick off your 'GREEN' and 'RED' anodes. Most Bicolor LEDs I've seen have a common cathode, so that (center) wire is ground.? ?? ? The PTT Relay is right in front (and down a bit) from the PTT connector. PIN 1 is 'down' & 'right' (if you're looking at the wireup.html page).
socket) Pin 16 is ground. You can either run it to a connector and 'crazy glue' or hot-glue to the PCB just underneath (and to the right of) the power connector - or, you can just run them in the free-air, maybe use some shrink tubing to keep them together. Just run them to your Bicolor LED. ? Mike Y |
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Sorry guys , heres the foto attached
Hi , You may see the attached foto , zoom in to see the red & green wires soldered to the DIP relay points Green for Rx and Red for Tx which is fed to the dual color LED ( three terminal type) the centre goes thru a 680 ohms resisitor to gnd. happy homebrewing best 73 Pop VU2POP From: BITX20@... [mailto:BITX20@...] Sent: Thursday, January 05, 2017 8:49 AM To: BITX20@... Subject: [BITX20] Re: LED for XMIT indication Well, I'm not sure photos would do, and it might take several. Plus there's 20 minutes of disassembly and re-assembly - it's screwed to the box...! However if you look at the schematic - lower left: ... you'll see the PTT and the 'main' relay - Pins 1 and 3 are RX+12V and TX+12V, respectively. They're even LABELLED on the schematic as RX and TX! They're not labelled on the PCB, but you can even test this with a voltmeter. Pin 1 will be +12 during receive. PTT and it will drop and TX (Pin 3) will pop up to +12. Pick off your 'GREEN' and 'RED' anodes. Most Bicolor LEDs I've seen have a common cathode, so that (center) wire is ground. You can pick up GROUND from this same relay - Pin 16 of the relay is ground. An even better picture can be seen from the 'wireup' page: The PTT Relay is right in front (and down a bit) from the PTT connector. PIN 1 is 'down' & 'right' (if you're looking at the wireup.html page). There's no need to desolder or remove the relay. Just go underneath and, strip your wires SHORT. You just need like 3 or 4 mm. Just solder to where the relay socket pins are soldered (remember they're 'reversed' on the bottom) - Pin 1 - RX, Pin 2 - TX, Pin 16 (which is opposite from Pin1 - it's a 16-pin socket) Pin 16 is ground. You can either run it to a connector and 'crazy glue' or hot-glue to the PCB just underneath (and to the right of) the power connector - or, you can just run them in the free-air, maybe use some shrink tubing to keep them together. Just run them to your Bicolor LED. Hope that helps. Now - if I have some time this weekend, I'll snap some photos. Mike Y [Non-text portions of this message have been removed] |
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开云体育That is nice looking case, Pop. Can you advise as to its source. 73 Bill, VK7MX On 5/01/2017 4:32 PM, 'VU2POP'
vu2pop@... [BITX20] wrote:
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Paul Chebi
In one of my earlier Bitx's I picked up by inducing into a couple of turns on on one of the final transformers/filters rectified it with a 1048 diode and fed it into an led with a resistor.similar to a "Peack Detector" circuit. This led will give you an indication of not only Xmit but a relative indication of the Transmitted power by the brightness of the led. My 2 cents. Paul Chebi |
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M Garza
Paul, I was going chime in with the same kind of suggestion.? Adding in a variable resistor, you could power a simple xmit meter.? A relay could be run off of the ptt switch to toggle it between s meter and output meter. Just my plan, once my bitx arrives. 73s Marco Garza ?(KG5PRT) On Jan 5, 2017 7:43 AM, "Paul Chebi paul.chebi@... [BITX20]" <BITX20@...> wrote:
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Pop, thanks for uploading the photo, I think adding the dual LED is a great idea. I wish I had a case like yours too! :-)) Roy WA0YMH On Jan 4, 2017 11:32 PM, "'VU2POP' vu2pop@... [BITX20]" <BITX20@...> wrote:
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开云体育Go to yahoo page for photo ? ? From: BITX20@... [mailto:BITX20@...]
Sent: Thursday, January 05, 2017 2:36 PM To: BITX20@... Subject: [BITX20] Re: LED for XMIT indication ? ? why can i not see the photo ??? ?
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开云体育You can access this file at the URL: ? From: BITX20@... [mailto:BITX20@...]
Sent: Thursday, January 05, 2017 2:41 PM To: BITX20@... Subject: RE: [BITX20] Re: LED for XMIT indication ? ? Go to yahoo page for photo ? ? From: BITX20@... [mailto:BITX20@...] ? ? why can i not see the photo ??? ? ?
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开云体育Hi Bill Yea I made a few and many wanted them so made some more You can see my FB page for more pictures Tnx 73 Pop VU2POP ? From: BITX20@... [mailto:BITX20@...]
Sent: Thursday, January 05, 2017 12:47 PM To: BITX20@... Subject: Re: [BITX20] Re: LED for XMIT indication ? ? That is nice looking case, Pop. Can you advise as to its source. 73 Bill, VK7MX ? On 5/01/2017 4:32 PM, 'VU2POP' vu2pop@... [BITX20] wrote:
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开云体育Thanks Pop. I'll ask the xyl to bring up your FB pages for me to look at, as I don't use FB myself. 73 Bill, VK7MX On 6/01/2017 2:48 PM, 'VU2POP'
vu2pop@... [BITX20] wrote:
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Joel Caulkins/N6ALT