Re: Nearly non-existent output power, no mod
Excellent line of investigation to follow.? Having replaced the finals (from Mouser) with predictably no change, I swapped out the Nano. New, known supplier, etc. No change.
The relay power at K1 - K3 changes with band selection so unless a relay is stuck, the mystery
just gets deeper.?? These are replacement Axicon relays, though anything can fail......
Ted
K3RTA
-Ted
|
Re: Wired up Bitx40 and it doesn't work!
Jerry,
Thank you; I'll try those steps. 73, Mark/WU6R
On September 12, 2019 at 3:21 PM, "Jerry Gaffke via Groups.Io" <jgaffke@...> wrote: Mark,
>>? I double checked for polarity being backwards and it is wired correctly...
>? ? The bench power supply is outputting 12v and 2 amps, but at the bitx the voltage drops to 0.49v
So, you measure 12v across the power supply and at the same time you measure 0.49v
across the Bitx40?? Then somewhere there is 11.51v drop across a bad connection,
you should be able to find that with a voltmeter.
If that power supply is sending out 2 Amps, that means 2 amps * 11.51 volts = 23 Watts of power
getting dissipated across that bad connection, and it is smoking hot.
I doubt that is the case.
My guess is that you see 12v at the power supply until you turn on the Bitx40,
at which point the power supply goes into current limiting and drops to around 0.49v.
Try unplugging PA-PWR (which gives 12v to the IRF510) and unplugging the Raduino.
Does it still drop to 0.49v?
Then something is dissipating 2 amps * 0.49v = 1 Watt, and if you feel around
the board with your fingers you will probably find something that's getting warm.
And that will be where the fault is.
If that doesn't find it, then disconnect stuff (with power off) until the voltage at the Bitx40 pops up to?
12v where it should be when you turn the power supply back on.??
Verify that the TX power rail has 0.0 volts on it (relay K1 is not stuck on).
If so, then the fault is in either on the 12v rail or the RX rail, as labeled in the schematic.
I assume you still see something like 0.49v on the 12v and RX rails when power is on,
perhaps somewhat less due to voltage loss with 2 Amps flowing through the power supply
wires and board traces.
You may be able to find the fault by measuring all points in the schematic labeled as either RX or +12v,
the point with the lowest voltage on it (some small fraction of a volt) should be near the fault.
If that doesn't do it, you may have to start removing parts or cutting traces to all places?
labeled RX and +12v in the schematic.? You know you are very close when you cut a portion
of the circuit out and the power supply now goes up to 12v when turned on.
Good luck!
Jerry, KE7ER
|
Re: Wired up Bitx40 and it doesn't work!
Mark,
>>? I double checked for polarity being backwards and it is wired correctly...
>? ? The bench power supply is outputting 12v and 2 amps, but at the bitx the voltage drops to 0.49v
So, you measure 12v across the power supply and at the same time you measure 0.49v
across the Bitx40?? Then somewhere there is 11.51v drop across a bad connection,
you should be able to find that with a voltmeter.
If that power supply is sending out 2 Amps, that means 2 amps * 11.51 volts = 23 Watts of power
getting dissipated across that bad connection, and it is smoking hot.
I doubt that is the case.
My guess is that you see 12v at the power supply until you turn on the Bitx40,
at which point the power supply goes into current limiting and drops to around 0.49v.
Try unplugging PA-PWR (which gives 12v to the IRF510) and unplugging the Raduino.
Does it still drop to 0.49v?
Then something is dissipating 2 amps * 0.49v = 1 Watt, and if you feel around
the board with your fingers you will probably find something that's getting warm.
And that will be where the fault is.
If that doesn't find it, then disconnect stuff (with power off) until the voltage at the Bitx40 pops up to?
12v where it should be when you turn the power supply back on.??
Verify that the TX power rail has 0.0 volts on it (relay K1 is not stuck on).
If so, then the fault is in either on the 12v rail or the RX rail, as labeled in the schematic.
I assume you still see something like 0.49v on the 12v and RX rails when power is on,
perhaps somewhat less due to voltage loss with 2 Amps flowing through the power supply
wires and board traces.
You may be able to find the fault by measuring all points in the schematic labeled as either RX or +12v,
the point with the lowest voltage on it (some small fraction of a volt) should be near the fault.
If that doesn't do it, you may have to start removing parts or cutting traces to all places?
labeled RX and +12v in the schematic.? You know you are very close when you cut a portion
of the circuit out and the power supply now goes up to 12v when turned on.
Good luck!
Jerry, KE7ER
|
Re: Is there a Raduino replacement with supply voltage, FWD & REF readings ?
Thanks I'm using the resistors that came with the kit. At 81 I think I'm Loosing It. 73 Jim
----- Original Message ----- From: Michael Hagen via Groups.Io <motdog@...> To: [email protected]Sent: Thu, 12 Sep 2019 12:03:27 -0400 (EDT) Subject: Re: [BITX20] Is there a Raduino replacement with supply voltage, FWD & REF readings ?
Relay K1 has 12v
connected to Tx or Rx.?? You can get it off the schematic
anywhere Tx or Rx is connected.
Use a current limiting
resistor for Led indicators. Mike, WA6ISP
On 9/12/2019 8:46 AM, James Baird
wrote:
Can someone Please tell me where the TX-RX on the LED hooks
up on the uBITX Board? Thanks?? Jim Baird W5OMM HOT IN TEXAS
----- Original Message -----
From: Razvan Fatu <razvanfatu@...>
To: [email protected]
Sent: Thu, 12 Sep 2019 06:45:53 -0400 (EDT)
Subject: Re: [BITX20] Is there a Raduino replacement with supply voltage, FWD & REF readings ?
Thank you for the replies.
I've looked at the CEC and JackAl expansions, they are nice
but add unnecessary complexity for this specific purpose and
neither seems to have all these minor but specific features I'm
looking for. Looking for a "less is more" approach if possible.
@ John, thank you for all the information, that's very close
to what I'm looking for. I like the way you use the limited
display area, I think this is quite close to what I need. I need
to spend a bit of time on it.
Razvan M0HZH
--
Mike Hagen, WA6ISP
10917 Bryant Street
Yucaipa, Ca. 92399
(909) 918-0058
PayPal ID "MotDog@..."Mike@...
|
Never used V3 uBitx Board Available
I have a never used - never powered uBitx version 3 board available for sale for $50 plus shipping - US only. If you ever wanted a spare, now is the time. First come, first serve. I accept payment by PayPal. Respond direct to me via the links below the message.
73,
W7DAO
|
Re: Compliance Summary - other radios
Hi Allison, i did get the prebuilt band pass filter from ebay.? Wondering if you have any suggestions to mod the KL-203 as well as how to mod it to be more sensistive to lower power e.g. from softrock <1w; I am able to trigger AM but not via SSB.
|
Re: CB amplifiers RM-Italy KL203P
I did get the KL203; not bad of course low pass filtering is required.? It works with 20m up. power mod is required and will make it once i get the caps 1200pf/50v for C14.
For softrock no lock; SSB output is too low to trigger it; not sure if anyone has thoughts to make the input power mod?
|
Yes agreed.
I got it but no luck - the power from softrock is too low to trigger the amp to transmit. Not sure if anyone knows how to mod it.? If I use AM,? it does trigger the amp.
Sajid
|
Re: Fuses, diodes and switches
#ubitx
Like Ian, I think the uBitx main rail is a good candidate for a series diode.
We don't care much if we lose a half volt there.
The hfsignals.com wireup diagram shows a shunt diode that conducts
if the power supply is hooked up backwards, but doesn't bother to show a fuse.
This is definitely a case where you absolutely need a fuse in front of the diode.
And the diode should be Schottky (as supplied with the kit) so it has a?
very low voltage drop when it does conduct.
As I said previously, there's hundreds of ways to do this.
Jerry
On Thu, Sep 12, 2019 at 09:44 AM, Jerry Gaffke wrote:
A series combination of a 0.5A fuse and a diode goes from that switch to the main 12v into the uBitx.
|
0dBm and -60dBm calibration
Hi all
Possibly interesting for people with an Antuino who want to check the calibration; or many other pieces of test equipment - I built an interesting 7MHz signal generator with very accurate 0dBm and -60dBm reference outputs yesterday. I made a YouTube video about it see?
73 Hans G0UPL
|
Re: New wiring diagram version
? Adrien,? feel that t is not a good idea to switch the negative power like you ask abot.
?A: is not the common practice. ?B: if the B+ (12 VC) and the PA + are different voltags, there is, IMO, a voltage differential between the B+ an PA +, so would possibly be some power feeding a part of the unit. That might or might not be a problem, and possible drain if running from batteries.
|
Re: Is there a Raduino replacement with supply voltage, FWD & REF readings ?
toggle quoted message
Show quoted text
----- Original Message ----- From: Michael Hagen via Groups.Io <motdog@...> To: [email protected]Sent: Thu, 12 Sep 2019 12:03:27 -0400 (EDT) Subject: Re: [BITX20] Is there a Raduino replacement with supply voltage, FWD & REF readings ?
Relay K1 has 12v
connected to Tx or Rx.?? You can get it off the schematic
anywhere Tx or Rx is connected.
Use a current limiting
resistor for Led indicators. Mike, WA6ISP
On 9/12/2019 8:46 AM, James Baird
wrote:
Can someone Please tell me where the TX-RX on the LED hooks
up on the uBITX Board? Thanks?? Jim Baird W5OMM HOT IN TEXAS
----- Original Message -----
From: Razvan Fatu <razvanfatu@...>
To: [email protected]
Sent: Thu, 12 Sep 2019 06:45:53 -0400 (EDT)
Subject: Re: [BITX20] Is there a Raduino replacement with supply voltage, FWD & REF readings ?
Thank you for the replies.
I've looked at the CEC and JackAl expansions, they are nice
but add unnecessary complexity for this specific purpose and
neither seems to have all these minor but specific features I'm
looking for. Looking for a "less is more" approach if possible.
@ John, thank you for all the information, that's very close
to what I'm looking for. I like the way you use the limited
display area, I think this is quite close to what I need. I need
to spend a bit of time on it.
Razvan M0HZH
--
Mike Hagen, WA6ISP
10917 Bryant Street
Yucaipa, Ca. 92399
(909) 918-0058
PayPal ID "MotDog@..."Mike@...
|
Re: Wired up Bitx40 and it doesn't work!
The bench power supply is outputting 12v and 2 amps, but at the bitx the voltage drops to 0.49v --
|
Re: Wired up Bitx40 and it doesn't work!
I double checked for polarity being backwards and it is wired correctly... --
|
Re: Fuses, diodes and switches
#ubitx
The diode is there to "protect" against reverse polarity and as it is wired directly across the supply and reverse biased,the circuit will effectively short circuit the supply if the supply is connected the wrong way round.Problem with this are that too large
a current will destroy the diode thus removing any protection. A simple and more safe approach is to put a diode in series with each supply line allowing current to pass if connected correctly and block it if reversed.The diodes need to be rated at say 2amps
and 4 amps if using separate supplies for the PA and the remainder of the circuit.The diode may drop up to 0.5v so a slight rise in power supply is to be considered.Only use appropriate sized fuses which should be the fast blow type.? Ian M0IDR
toggle quoted message
Show quoted text
I recently wired up my uBITX. I've attached a photo that shows how I wired up the DC socket with some fuses. I used two fuses: one 0.5 A fuse for the main board (red wire) and one 2.0 A fuse for the PA power (brown wire). Before I started, I was only able
to find one photo on the Internet showing a uBITX wired up with two fuses and, due to the way the picture was cropped, it wasn't entirely clear to me just exactly what wires went where and how the diode was wired with the fuses.?
As you can see in my photo (hopefully), starting at the P1 connector, the black wire is soldered to the (-) pin on the DC connector. The brown wire goes to one pin of a fuse holder (with the 2.0 A fuse), and then another brownish wire goes from the other pin
on that fuse holder to the (+) pin on the DC connector. The red wire from the P1 connector goes to one of the "on/off" pins on the back of the volume control pot (not shown). Another red wire goes from the other "on/off" pin on the back of the volume control
pot (not shown) back to one pin of another fuse holder (with the 0.5 A fuse), and then another red wire goes from the other pin on that fuse holder to the (+) pin on the DC connector (with the brown wire). I have soldered the diode across the (+) and (-) pins
on the DC connector, as shown and described in the wire up instructions -- which puts the diode *before* the fuses. This is how the latest "Wiring Diagram Ubitx V5 V2.0.pdf" shows it, and it's also shown this way on the uBITX Assembly wiki.
However, in several messages in this forum, I have seen folks say the diode should be *after* the fuses. Would someone please explain why the diode should go behind the fuses (and is it "should go behind" or "must go behind")? Also, could someone please describe
or show specifically where, in relation to the fuses, the diode would be soldered so that it's *after* the fuses? Like I said, the latest wiring diagram?shows the diode wired to the pins on the DC connector *before* the fuses.
Also, the way I've wired the fuse for the PA power seems to bypass the on/off switch and, thus, regardless of whether the on/off switch is on or off, power is supplied to the PA. Is this how others see this? Should I also have the brown wires going to the volume
control pot on/off pins, too, just like the red wires? Or, is there another way I can wire this so that no power will be supplied to the board or the PA while the on/off switch is off?
Btw, I've successfully powered on the uBITX and everything seems to be working properly (although, there is so much noise around here I haven't actually been able to hear much of anything).
Anyway, any suggestions/comments regarding the fuses and diode are appreciated.
|
Re: Fuses, diodes and switches
#ubitx
Nothing terribly wrong with what you have done, seems better than most I've seen described here.
But I'd have a switch in line with the PA-PWR, as you suggest.??
When the power switch for the rig is off, the rig should be completely off (in my opinion).
The reason to have a fuse before the switch instead of after is so you will blow the fuse
if you accidentally short out the switch with a screwdriver or something.
Not a big deal to have the fuse after the switch, such an accident should not blow up the uBitx.
And if the power supply is properly designed to deal with over-current, it should not be damaged.
Though if the supply is big enough, you might melt a perfectly good screwdriver.
On my rig, I have a 3A fuse in line with main power coming into the rig, it then goes to the main power switch.
A series combination of a 0.5A fuse and a diode goes from that switch to the main 12v into the uBitx.
Also from that first switch, a wire to a second switch to power the PA-12v rail into the IRF510's.
Reverse protection for the IRF510's is not needed, they have their own intrinsic reverse diode,
it will conduct if the power supply leads are reversed and blow the 3A fuse up front.
Hopefully that fuse will blow before the traces into the IRF510's do.
The second switch is very handy for testing the transmitter.
With that switch off I don't need to worry about having the dummy load
while working on everything up through the driver stages.
Actually, instead of a diode, I use an LM2940CT-12 low dropout regulator.
It gives reverse polarity protection with about the same dropout voltage loss,
and allows me to safely feed the rig more than 12v.??
If you do choose to use a diode, a relatively wimpy one like a 1n4148?
may work well enough as a roughly 0.5 Amp fuse, then you only have
one fuse of 2 or 3 Amps up front.? I have not tried this.
?
There are probably hundreds of different ways to do this.
Especially if you plan to sometimes have an entirely different power supply
of higher voltage to feed PA-PWR.
Jerry
toggle quoted message
Show quoted text
On Thu, Sep 12, 2019 at 09:12 AM, DD5ET wrote:
I recently wired up my uBITX. I've attached a photo that shows how I wired up the DC socket with some fuses. I used two fuses: one 0.5 A fuse for the main board (red wire) and one 2.0 A fuse for the PA power (brown wire). Before I started, I was only able to find one photo on the Internet showing a uBITX wired up with two fuses and, due to the way the picture was cropped, it wasn't entirely clear to me just exactly what wires went where and how the diode was wired with the fuses.?
As you can see in my photo (hopefully), starting at the P1 connector, the black wire is soldered to the (-) pin on the DC connector. The brown wire goes to one pin of a fuse holder (with the 2.0 A fuse), and then another brownish wire goes from the other pin on that fuse holder to the (+) pin on the DC connector. The red wire from the P1 connector goes to one of the "on/off" pins on the back of the volume control pot (not shown). Another red wire goes from the other "on/off" pin on the back of the volume control pot (not shown) back to one pin of another fuse holder (with the 0.5 A fuse), and then another red wire goes from the other pin on that fuse holder to the (+) pin on the DC connector (with the brown wire). I have soldered the diode across the (+) and (-) pins on the DC connector, as shown and described in the wire up instructions -- which puts the diode *before* the fuses. This is how the latest "Wiring Diagram Ubitx V5 V2.0.pdf" shows it, and it's also shown this way on the uBITX Assembly wiki.
However, in several messages in this forum, I have seen folks say the diode should be *after* the fuses. Would someone please explain why the diode should go behind the fuses (and is it "should go behind" or "must go behind")? Also, could someone please describe or show specifically where, in relation to the fuses, the diode would be soldered so that it's *after* the fuses? Like I said, the latest wiring diagram?shows the diode wired to the pins on the DC connector *before* the fuses.
Also, the way I've wired the fuse for the PA power seems to bypass the on/off switch and, thus, regardless of whether the on/off switch is on or off, power is supplied to the PA. Is this how others see this? Should I also have the brown wires going to the volume control pot on/off pins, too, just like the red wires? Or, is there another way I can wire this so that no power will be supplied to the board or the PA while the on/off switch is off?
Btw, I've successfully powered on the uBITX and everything seems to be working properly (although, there is so much noise around here I haven't actually been able to hear much of anything).
Anyway, any suggestions/comments regarding the fuses and diode are appreciated.
|
Re: New wiring diagram version
Putting things like diodes and switches on the ground return back to the power supply
is a bad idea.? There are many other ways that the ground return could be completed.
For example, some power supplies will have the 12v ground return connected to the?
electrical safety ground of the three wire power plug into the wall socket.?
And your antenna coax outer braid should have a good solid earth ground as well.
So there's always a completed ground return, and the rig is always on.
A connection from a PC USB port into the Raduino could complete the ground return,
putting 3+ amps through those wires might even damage the PC motherboard.
?
Perhaps you have it powered from an automotive electrical system.
Having the rig chassis touch the any metal in the vehicle would turn the rig on.
The diode in the ground return would probably offer adequate reverse polarity
protection for the uBitx.? ?But I wouldn't do it.
For one, my brain doesn't work that way.
For another, all of the power supply return current might be going through your
antenna coax braid or through your computer's USB cable, since that may well
have a lower voltage drop than the 0.7 volts across a forward biased silicon diode.
Could cause trouble.? Better to spend an extra $0.02 on a second diode.
Jerry, KE7ER
toggle quoted message
Show quoted text
On Thu, Sep 12, 2019 at 02:21 AM, Adrien F4IJA wrote:
Do you think it's a good idea to put the S1 switch (the volume switch on GND instead of 12V ?
This way, it'll cut everything when powered off.
Thanks,
--
73's
Adrien F4IJA
|
Fuses, diodes and switches
#ubitx
I recently wired up my uBITX. I've attached a photo that shows how I wired up the DC socket with some fuses. I used two fuses: one 0.5 A fuse for the main board (red wire) and one 2.0 A fuse for the PA power (brown wire). Before I started, I was only able to find one photo on the Internet showing a uBITX wired up with two fuses and, due to the way the picture was cropped, it wasn't entirely clear to me just exactly what wires went where and how the diode was wired with the fuses.? As you can see in my photo (hopefully), starting at the P1 connector, the black wire is soldered to the (-) pin on the DC connector. The brown wire goes to one pin of a fuse holder (with the 2.0 A fuse), and then another brownish wire goes from the other pin on that fuse holder to the (+) pin on the DC connector. The red wire from the P1 connector goes to one of the "on/off" pins on the back of the volume control pot (not shown). Another red wire goes from the other "on/off" pin on the back of the volume control pot (not shown) back to one pin of another fuse holder (with the 0.5 A fuse), and then another red wire goes from the other pin on that fuse holder to the (+) pin on the DC connector (with the brown wire). I have soldered the diode across the (+) and (-) pins on the DC connector, as shown and described in the wire up instructions -- which puts the diode *before* the fuses. This is how the latest "Wiring Diagram Ubitx V5 V2.0.pdf" shows it, and it's also shown this way on the uBITX Assembly wiki. However, in several messages in this forum, I have seen folks say the diode should be *after* the fuses. Would someone please explain why the diode should go behind the fuses (and is it "should go behind" or "must go behind")? Also, could someone please describe or show specifically where, in relation to the fuses, the diode would be soldered so that it's *after* the fuses? Like I said, the latest wiring diagram?shows the diode wired to the pins on the DC connector *before* the fuses. Also, the way I've wired the fuse for the PA power seems to bypass the on/off switch and, thus, regardless of whether the on/off switch is on or off, power is supplied to the PA. Is this how others see this? Should I also have the brown wires going to the volume control pot on/off pins, too, just like the red wires? Or, is there another way I can wire this so that no power will be supplied to the board or the PA while the on/off switch is off? Btw, I've successfully powered on the uBITX and everything seems to be working properly (although, there is so much noise around here I haven't actually been able to hear much of anything). Anyway, any suggestions/comments regarding the fuses and diode are appreciated. 
|
Re: Is there a Raduino replacement with supply voltage, FWD & REF readings ?
Relay K1 has 12v
connected to Tx or Rx.?? You can get it off the schematic
anywhere Tx or Rx is connected.
Use a current limiting
resistor for Led indicators.
Mike, WA6ISP
On 9/12/2019 8:46 AM, James Baird
wrote:
Can someone Please tell me where the TX-RX on the LED hooks
up on the uBITX Board?
Thanks?? Jim Baird W5OMM
HOT IN TEXAS
----- Original Message -----
From: Razvan Fatu <razvanfatu@...>
To: [email protected]
Sent: Thu, 12 Sep 2019 06:45:53 -0400 (EDT)
Subject: Re: [BITX20] Is there a Raduino replacement with supply
voltage, FWD & REF readings ?
Thank you for the replies.
I've looked at the CEC and JackAl expansions, they are nice
but add unnecessary complexity for this specific purpose and
neither seems to have all these minor but specific features I'm
looking for. Looking for a "less is more" approach if possible.
@ John, thank you for all the information, that's very close
to what I'm looking for. I like the way you use the limited
display area, I think this is quite close to what I need. I need
to spend a bit of time on it.
Razvan M0HZH
--
Mike Hagen, WA6ISP
10917 Bryant Street
Yucaipa, Ca. 92399
(909) 918-0058
PayPal ID "MotDog@..."
Mike@...
|
Re: Is there a Raduino replacement with supply voltage, FWD & REF readings ?
Can someone Please tell me where the TX-RX on the LED hooks up on the uBITX Board? Thanks? Jim Baird W5OMM HOT IN TEXAS
----- Original Message ----- From: Razvan Fatu <razvanfatu@...> To: [email protected]Sent: Thu, 12 Sep 2019 06:45:53 -0400 (EDT) Subject: Re: [BITX20] Is there a Raduino replacement with supply voltage, FWD & REF readings ?
Thank you for the replies.
I've looked at the CEC and JackAl expansions, they are nice but add unnecessary complexity for this specific purpose and neither seems to have all these minor but specific features I'm looking for. Looking for a "less is more" approach if possible.
@ John, thank you for all the information, that's very close to what I'm looking for. I like the way you use the limited display area, I think this is quite close to what I need. I need to spend a bit of time on it.
Razvan M0HZH
|
Ted
Mark WU6R