Date   
Re: Wiring encoder

Jack, W8TEE
 

All:

Before messing around with the unsoldering/resoldering the connections, if you have the Arduino IDE installed and are comfortable with it, load the ubitx_20.ino source code file and locate line 75-76:

#define ENC_A (A0)
#define ENC_B (A1)

Try reversing these symbolic constants:

#define ENC_B (A0)
#define ENC_A (A1)
and see if that restores the proper rotation. Mine is all bundled up for a pending presentation, and I don't want to unpack it.

Jack, W8TEE


From: ekelley <ekelley828@...>
To: BITX20@groups.io
Sent: Tuesday, January 2, 2018 1:07 AM
Subject: [BITX20] Wiring encoder

A word of caution when wiring the encoder. The schematic on page one
has the encoder wiring reversed. Don't wire it up by the schematic
use the picture, you will see that the red and yellow wires are reversed
and the black and brown are reversed. I made the mistake of wiring everything
up using the schematic. When tuning my frequency goes down with clockwise
rotation of encoder. Goes up with counter-clockwise rotation.
Ed



Virus-free. www.avast.com

Re: BCI filter question.

Karl Heinz Kremer, K5KHK
 

For a cheap BCI filter, take a look here (it's the first article in this document): http://www.qrpforum.de/index.php?page=Attachment&attachmentID=16959&h=269da5721a0d272fc6ce550399700bfc9d9a8155

For a simpler, but slightly more expensive solution, see here: http://www.qrpme.com/?p=product&id=BCI

If you want something you can leave in during transmit, take a look here: http://vk3il.net/projects/broadcast-band-filter/

You an also calculate your own, all you need is a high-pass filter that cuts off just above the AM band. As Gordon suggested, a notch filter might be a good idea as well. 
--
Karl Heinz - K5KHK

Re: Tell me your favorite uBitx mods

jamesrocks4ever@...
 

Maybe an Si570 for low phase noise. Serial connection for possible remote operation with the rtl and web sdr on a tablet. I have been thinking about laying out modules in 0805 two sided boards to make it fit in a smaller package. 
 I was actually waiting to get the ubitx until the first wave of mods. I’ve had the bitx out of a case more than in one doing mods.

James

Sent from my iPhone

On Dec 31, 2017, at 20:29, Diver Martin <diver.martin@...> wrote:

Hello all,

As I'm doing a motherboard mod, I'm looking to incorporate a bunch of mods into one PCB.  Right now, what I've got going are the following:

* A tuner + SWR Bridge (phase detector maybe?)
* A spot for an RTL-SDR (blogV3) dongle
* AGC Modifications
* Integrating LCD and headphone/mic/BNC/Power/etc jacks into the PCB

Other things I've thought about, space depending:

*Adding in footprints for a chinese AD9850 DDS module for one of the clock signals

I would like to hear the top mods you've done, and what you'd love to see integrated into a motherboard PCB that fits on top of the uBitx.  Battery charger?  Battery adapter? I dunno, bring it on!  If you have a favorite AGC mod, please tell me about it, and make some suggestions as well.  This is not promising to be a cheap kit, and full of SMT, but something I might make available.

Happy new year,

--
Martin Held - AE7EU
http://ae7eu.com/
-------------------------------------------------------------------------------
If there aren't any questions, then what is there to learn?

Re: No TX #ubitx

 

Joe had earlier mentioned as far I remember that he had done the TX
current bit. So we have to look elsewhere!

Raj

At 02-01-2018, you wrote:
No, there are 3 wires to the power plug, I think they are Black (0v), Red
(12v Rx power) and Brown (12v/24V PA power). The Brown and Red wires
should both be connected to the 12V power via the on/off switch on the
volume control.

The two supply wires allow you to feed a different (higher) voltage to the
PA transistors to achieve higher output power.

It just sounds like there is no power being applied to the PA stage.

By PA supply wire, do you mean the wire to the speaker/headphone jack? If
so, yes that's hooked up. It's working as a receiver (i.e. I'm copying
activity on the bands) playing through a pair of headphones.

Re: BCI filter question.

Gordon Gibby <ggibby@...>
 

so....that sounds like even with harmonic suppression, you have SIGNIFICANT energy coming at your on the harmonics of their primary frequency.....


hopefullly it ISNT being created within some nonlinear junction in your own radio....the way to prevent that would be a high pass filter in your transmission line designed to pass anything above, say 2 MHz and not pass stuff below that.    I'm guessing you already have those kinds of filters?


beyond that, the actual hamonic radiated energy generated by THEIR TRANSMITTER  is a fact of life, and you aren't going to be able to receive much (other than them) on those frequencies....


if you try and builld a notch filter (high Q, narrow bandwidth) for each of their harmonics youll hear them less....but you'll also hear other people near those frequencies less also....





From: BITX20@groups.io <BITX20@groups.io> on behalf of KG5NII <kg5nii@...>
Sent: Tuesday, January 2, 2018 8:52 AM
To: BITX20@groups.io
Subject: [BITX20] BCI filter question.
 

I am thinking seriously about experimenting with the uBitX but am wondering in advance if someone could suggest  a good broadcast band filter I can build that is known to be effective. I live less than 1 mile (1.6 km) from a 50 kW AM broadcast station transmitting on 1180 kHz. I know this will be a problem with on the uBitX as even on mid, high end commercial ham rigs I get significant interference on 3540, 7040, 14160 kHz and so on.   In fact, I'd probably want to build an additional one for my Yaesu.  I know there are a lot of circuits out there for BCI filters but that doesn't necessarily mean they are or would be effective.  Cost is a major concern,  and commercial filter units seem to be rather pricey, but on the other hand, purchasing the components, etc may not necessarily be cost effective either given the somewhat high cost of shipping and given that  not everything could necessarily be purchased from one place, thereby rising costs even more.    I'd probably want to build one for the uBitX and one for my 100W Yaesu  just to give it over and done with.  There is not a day that goes by that I do not wish the four AM 1180 transmitter  towers down the road from me  are flattened by a tornado until I realize that would only be a temporary reprieve at best  but building, installing some good filters will be a permanent one.  


So advice please.


Thanks.

Ron, KG5NII



Re: No TX #ubitx

Reid Campbell
 

No, there are 3 wires to the power plug, I think they are Black (0v), Red
(12v Rx power) and Brown (12v/24V PA power). The Brown and Red wires
should both be connected to the 12V power via the on/off switch on the
volume control.

The two supply wires allow you to feed a different (higher) voltage to the
PA transistors to achieve higher output power.

It just sounds like there is no power being applied to the PA stage.

By PA supply wire, do you mean the wire to the speaker/headphone jack? If
so, yes that's hooked up. It's working as a receiver (i.e. I'm copying
activity on the bands) playing through a pair of headphones.

Re: No TX #ubitx

Gordon Gibby <ggibby@...>
 

​no, he means the 2nd  connection for power to the power amplifier.


On the bitx40 it is a separate 2-conductor plug/pins


on the ubitx it is an additional wire on the 3-wire power connector....


if you don't have power going to the pwer amplifier....won't have any output


IN TX, the heatsink should go to +12 V DC.  you can check the tab of the irf510 with  voltmeter




gordon



From: BITX20@groups.io <BITX20@groups.io> on behalf of joe kallo <quietglow@...>
Sent: Tuesday, January 2, 2018 8:56 AM
To: BITX20@groups.io
Subject: Re: [BITX20] No TX #ubitx
 
By PA supply wire, do you mean the wire to the speaker/headphone jack? If so, yes that's hooked up. It's working as a receiver (i.e. I'm copying activity on the bands) playing through a pair of headphones.

Re: No TX #ubitx

joe kallo <quietglow@...>
 

By PA supply wire, do you mean the wire to the speaker/headphone jack? If so, yes that's hooked up. It's working as a receiver (i.e. I'm copying activity on the bands) playing through a pair of headphones.

BCI filter question.

KG5NII
 

I am thinking seriously about experimenting with the uBitX but am wondering in advance if someone could suggest  a good broadcast band filter I can build that is known to be effective. I live less than 1 mile (1.6 km) from a 50 kW AM broadcast station transmitting on 1180 kHz. I know this will be a problem with on the uBitX as even on mid, high end commercial ham rigs I get significant interference on 3540, 7040, 14160 kHz and so on.   In fact, I'd probably want to build an additional one for my Yaesu.  I know there are a lot of circuits out there for BCI filters but that doesn't necessarily mean they are or would be effective.  Cost is a major concern,  and commercial filter units seem to be rather pricey, but on the other hand, purchasing the components, etc may not necessarily be cost effective either given the somewhat high cost of shipping and given that  not everything could necessarily be purchased from one place, thereby rising costs even more.    I'd probably want to build one for the uBitX and one for my 100W Yaesu  just to give it over and done with.  There is not a day that goes by that I do not wish the four AM 1180 transmitter  towers down the road from me  are flattened by a tornado until I realize that would only be a temporary reprieve at best  but building, installing some good filters will be a permanent one.  


So advice please.


Thanks.

Ron, KG5NII



Re: No TX #ubitx

 

Joe,

If you have a radio to monitor in the shack, put a short 6" wire to C80 and see if you can hear yourself on a receiver.

If OK try the next stage C84.

Check all the DC voltages in the TX stages with PTT pressed and mic disconnected.

Raj

At 02-01-2018, you wrote:
Okay I fiddled with all the torroids with the key down and saw no evidence of shorts. Also no activity on the power meter. I tested tx in 80, 40 and 20m with the same results on all. I heard signals on 80&40 (it's too early for 20 here still). I didn't check solder continuity on the torroids as that will mean taking it apart. I'll do that next.

Also of note: I had the key down for 30-45 second periods while messing around and the finals transistors did not change temperature to the touch.

Re: No TX #ubitx

Reid Campbell
 

I got caught out by leaving the brown PA supply wire off while I got the
Rx working. Have you checked that?

Cheers

Reid Gi8TME/Mi0BOT

Okay I fiddled with all the torroids with the key down and saw no evidence
of shorts. Also no activity on the power meter. I tested tx in 80, 40 and
20m with the same results on all. I heard signals on 80&40 (it's too early
for 20 here still). I didn't check solder continuity on the torroids as
that will mean taking it apart. I'll do that next.

Also of note: I had the key down for 30-45 second periods while messing
around and the finals transistors did not change temperature to the touch.

Re: Tell me your favorite uBitx mods

Bob Benedict, KD8CGH
 

The present keying system doesn't work reliably. I have had problems with it and others have also reported problems. A fix has been suggested that uses the same analog multi level scheme, but I think a digital key interface would be more reliable. I see that you have included something in your schematic.

By narrower filter I meant an adjustable audio filter. I'm adding a Sotabeam dual bandwidth CW filter to mine with a 3 position switch. Position one is out (original SSB filter), two is Sotabeam wide and three is Sotabeam narrow. A handy feature is that the filter can activate an led when you are well tuned and I'm adding that. The filter is placed in line with the volume control. I'm also adding the PTT audio mute pop fix from the Wiki that grounds the same line from volume control. Both are on a piece of perf board attached by two of the nuts that hold the speaker.

An alternative audio filter could be a SCAF that goes on the audio output.

For digital modes an isolation transformer and either a VOX or CAT control for PTT.

Thanks for starting a Christmas list.

Re: BITX20 Ver3C SBL VFO

Mvs Sarma <mvs_sarma@...>
 

Congrats and best of 2018.

You could perhaps tailor the range by chaging the top and bottom resistors of the 10T potentiometer.
Reduce bottom resistor for further downing on lower side or increase to increase low end.

like wise, upper resistor increase causes lowwers the high end freq . and viceversa.

cheers
 sarma
 vu3zmv

On Tuesday 2 January 2018, 2:07:38 PM IST, Kevin Luxford <kbgluxford@...> wrote:


Building Sunil's kit. VFO completed. Lo freq = 3.957 MHz. Hi freq = 4.477 MHz. Range is a bit wider than I would like.  Will look at ways of restricting the range.  However the FLL makes it absolutely rock steady.  LED extinguishes in less than a second. Wound L4 with a slightly heavier guage wire that solders through the coating.  Had to wind the last few turns back over the earlier ones.  This will probably add a bit of capacitance in parallel to the inductance, but it seems to work OK.  Using RG316 which I have on hand instead of the RG174 supplied because longer interconnections seemed advantageous when testing and fiddling about. On to the next stage!

Re: Si5351/A Utility Console

Ken KM4NFQ <km4nfq@...>
 

Wow. Thanks. I just got a couple of Si5351As from http://www.qrp-labs.com/synth.html so I'm looking forward to trying your console, hopefully sometime in the near future. 73 Ken, KM4NFQ

On Mon, Jan 1, 2018 at 9:32 PM, Bruce MacKinnon KC1FSZ <bruce@...> wrote:
This has been very useful to me so I'll share it in case it is useful to others.

I have written an Arduino sketch that provides a simple command-line console (serial) to control most features of an Si5351/A.  This provides a very generic tool that can be used during the early phases of home-brew rig development when you just want to get the RF/IF chain up and running in a minimal way without fooling around with displays, encoders, Arduino coding, etc.  Just load up this sketch, connect the I2C pins to the Si5351/A, open he Serial Monitor (or other terminal program) and you're ready to start tuning.

There are some handy features that make it easy to deal with superhet math and filter pass-band tweaking. The details are here: https://github.com/brucemack/Si5351-Console.

I'm doing a scratch-build of the BITX-40 with some modifications so I've been using this sketch a lot.  For my BITX I use CLK0 for the VFO, CLK2 for the BFO, and CLK1 as an RF signal injector/tester.  Here is a video of the receive side up and running: https://www.youtube.com/watch?v=nueR5nY3wYc

Happy New Year and 73s,

Bruce KC1FSZ 


Re: No TX #ubitx

joe kallo <quietglow@...>
 

Okay I fiddled with all the torroids with the key down and saw no evidence of shorts. Also no activity on the power meter. I tested tx in 80, 40 and 20m with the same results on all. I heard signals on 80&40 (it's too early for 20 here still). I didn't check solder continuity on the torroids as that will mean taking it apart. I'll do that next.

Also of note: I had the key down for 30-45 second periods while messing around and the finals transistors did not change temperature to the touch.

Re: No TX #ubitx

 

Joe,

This means that you can ignore L1-L4 & T1 to T7 - these are common to TX and RX

Check T8 onwards.

Check TX on all the bands, the problem may be band specific.

Raj

At 02-01-2018, you wrote:
It does indeed receive.

I'll check out the toroids, thanks. It's funny you mention that as they looked a little flattened when I opened the kit.

Joe

Re: No TX #ubitx

joe kallo <quietglow@...>
 

It does indeed receive. 

I'll check out the toroids, thanks. It's funny you mention that as they looked a little flattened when I opened the kit.

Joe

BITX20 Ver3C SBL VFO

Kevin Luxford
 

Building Sunil's kit. VFO completed. Lo freq = 3.957 MHz. Hi freq = 4.477 MHz. Range is a bit wider than I would like.  Will look at ways of restricting the range.  However the FLL makes it absolutely rock steady.  LED extinguishes in less than a second. Wound L4 with a slightly heavier guage wire that solders through the coating.  Had to wind the last few turns back over the earlier ones.  This will probably add a bit of capacitance in parallel to the inductance, but it seems to work OK.  Using RG316 which I have on hand instead of the RG174 supplied because longer interconnections seemed advantageous when testing and fiddling about. On to the next stage!

Re: uBitx IRF510 to IRF510 physical measurement

John Backo
 

Bill:

That's a good heat-sink for the IRF510 pair. Just be wary of shorting the devices to ground.
Also note that pc board and plastics are a very poor conductor of heat -- if you are building a case from non-metallic
materials, be sure that the IRF510's are connected DIRECTLY to the metal, and not through
the wall of the enclosure. Also, ground the metal. Hi.

I have bought this kind of heat-sink as surplus. They are used on voltage converters and inverters,
especially in solar installations.

john
AD5YE

Re: uBitx IRF510 to IRF510 physical measurement

Prathap Naidu
 

Hi Bill

centre pin to centre pin is 34.5mm

best 73

Pop

VU2POP

 

From: BITX20@groups.io [mailto:BITX20@groups.io] On Behalf Of bill richardson
Sent: Sunday, December 31, 2017 10:20 PM
To: BITX20@groups.io
Subject: [BITX20] uBitx IRF510 to IRF510 physical measurement

 

looking to buy a large heatsink to use on my uBitx when it arrives. Can someone (that has a uBitx) measure on center to on center from one irf510 to the other.

looking at using this one:

Aluminum Heat Sink Heatsink Module Cooler Fin for High Power Amplifier Transistor Semiconductor Devices with Dense 24 pcs Fins 5.9"(L) x 2.3"(W) x 0.98"(H) 1pc/ 150 mm (L) x 59mm (W) x 25mm (H)

https://www.amazon.com/dp/B073VDVVP5/ref=cm_sw_r_cp_tai_xsrsAb5YJE73T

Thank you

Bill ng1p