Topics

Modular uBitx - "Ex: Harmonics"

Jack, W8TEE
 

Carl:

Some very good ideas.

I'm showing the Rev 2 JackAl board here, partly to show what we done, but also to show the mistakes we made along the way. (We're doing
Inline image
the Rev 4 board now.) First, we've taken the buck converter off simply because it was too fragile when adjusting...far to easy to rip the adjusting screw right off the board. Second, the 7W audio amplifier (big IC on lower left) is stupid for the nano acres it takes plus its cost. Most users have powered speakers or can easily add them. We don't have a direct I2C connection, but we do have an SPI interface for the touch screen display. (Our display handles the video processing.) The rest are connections that work through the exiting µBITX headers, which would not be the same for a new design. Still, the above is less than 100mm x 100mm and parts are being taken off. Obviously, we have the Si5351 chip onboard, but that probably should be on the main board. The SMD parts will be part of the PCB when sold.

To me, perhaps the most important thing we've done is bring out a bunch of pins, both digital and analog, for others to use. I hope the selected processor for such a project has a bunch available.

Jack, W8TEE



On Wednesday, August 15, 2018, 12:27:03 PM EDT, RCBoatGuy via Groups.Io <ijnfan-HamRadio@...> wrote:


Here's some features I'd like to see in any new design that shouldn't cost much, but would make life/testing/experimentation easier:

- Sockets for CPU boards on any new Raduino design.  (Teensyduino has this already, and I think the JackAl does, too)

- Sockets for relays, as these have been a frequent source of failure

- Move any pull-up resistors required onto the Raduino/Teensyduino/JackAl board and not rely on the user to wire them up.  Many users either failed to wire up the 4.7K external resistor correctly or had the connection fail later, causing the rig to immediately go into transmit on power-up.  This is easily avoided by having the required pull-ups on the Raduino/Teensyduino/JackAl board itself.

- Add 3-pin 0.1" input and output headers/jumpers to each section (Bi-di Amps, Audio Amp, Mic Amp, BPF, PA, LPF, etc) on a given board so that the given section can be isolated and tested independently.  For inputs to a section, 1st pin is output from prior section, 2nd pin is input to current section, 3rd pin is GND.   For outputs from a section, 1st pin is output from section, 2nd pin is input to next section, 3rd pin is GND.  Normal operation uses shorting jumpers across pins 1 and 2 to allow signals to flow thru, but jumpers can be removed and test inputs/outputs connected via molex/etc connectors to pins 2 and 3 (or to all 3 pins if desired).  This also makes it easier to replace a given section with an external circuit for experimentation/modification.

- Room for extra I2C headers on the Raduino (Teensyduino already has this, not sure about the JackAl) that the user can install later if desired

- Would be nice if the modular design had the PA on a separate board so different PAs can be used based on user preference.  Having different boards for a IRF510 PA, a RD16HHF1 PA, etc, would be nice as the user can pick and choose what they want, or build their own much easier.

- Support for adding additional BPF/LPF for those that want 160M, 6M, etc

- As for the LPF relays, I'd recommend using a relay scheme like that on the mcHF transceiver.  Their approach minimized the number of relays (only 4 DPDT relays needed for 4 filters), but still had filter inputs and filter outputs going to different relays.

- Design board so that the Raduino/Teensyduino/JackAl board has no obstructions from parts and/or connectors along the entire edge of the radio board.  The Teensyduino had to design in special cut-outs to use with the current uBitX due to obstructions. It would be nice if cut-outs like this were not needed in the future.

- Si5351 on main board, not on Raduino/Teensyduino/JackAl

That's my 2 cents.  Take it for what it's worth.  :)

73, 

Carl, K0MWC

Arv Evans
 

The idea of a "Modular uBITX" is interesting because with a full set of specs for each
module it might be possible for different persons or groups to concentrate on one module,
resulting in a group-designed transceiver.  This has potential to reduce design work from
"doing it all" to doing just a module that could be incorporated into the overall product.
But modular does imply added electrical and mechanical specifications for interfaces,
which could be either good or bad.

Arv
_._


On Wed, Aug 15, 2018 at 2:57 AM Gordon Gibby <ggibby@...> wrote:
Those are great ideas, but what about a limitation on cost? Should be under $140.


On Aug 15, 2018, at 04:42, Henning Weddig via Groups.Io <hweddig@...> wrote:

Nick,

I already started to do "my" improvement on the µBITX, but then stopped, after reading and trying to understand all the issues involved and going back to ideas about a spec and blocks to be designed.

As I am an retired electrical engineer specialized in RF and communication techology (I started my profesional career in 1980 at the company Hagenuk in Kiel Germany designing part of the ship´s main communication receiver RX 1001 and later RX1001M, then working on the RF part of the ST900 cordless telephone) 

As I posess a "good equipped home lab" witrh used commercial equipment (spectrum analysers, networt analyser, signal generators and so on), I can test my disgins properl.

Before going to design something  we first should think about a specifiaction and wirte it down. Yes I know seldom engineers like it,  but this will give some insight into what has to be designed. Very important are also level diagrammes of the bolocks involved to see if the to be designed unit will fulfill the desired spec.

From this point of view Glenn´s way of doing a new design in  first to test sub modules is a brilliant idea as it was also used in the industry (and my last occupation within a physics high energy research lab). We often only developed a single unit wioth the use of connectorized "Mini Circuit modules" and built into a case.

As SMD compoents are used the size of the "cheap" chinese pcb´s should be < 100 * 100 mm.

I believe that this forum including Farhan can and shuld be a good potential for an optimized new µBITX!

My previous ideas:

modular design on pcb´s (<100 * 100 mm)

frequency range 10 kHz to 30 MHz

first IF > 45 MHz (to avoid the 2*IF - LO problem) using four pole xtal filters  e.g. 70 MHz (if easily avaliable)? Another "popular IF could be 58 MHz or 58.1125 MHz (used in Hagenuks cordless phones) My be enough NOS filters are laying around.

1) receiver/exciter pcb

2) xtal filter board for the second IF (e.g. 5 MHz) with filters for SSB; AM; FM(?), CW

2) input lowpass filter (corner freq. 1.6 MHz) plus  overlapping bandpass filters (e.g. 1.6 - 4MHz; 4 - 8 MHz, 8 - 16 MHz; 16 - 30 MHz)

3) driver board

5) PA board

6) lpf´s

7) VSWR bridge

8) VFO (several SI5351 ? to avoid crosstalk between outputs of a single SI5351 driven from a single reference (TCXO; or VCXO which could be synchronized to a GPS reference?)

RF signals to be routed via SMA connectors

Of course AGC should be inclueded!

For the mic amp I remember that for maritime ship transmitters there is a requirement to limiting the max RF output via a Mic compressor. Chips like the SSM2167 could easily fulfill such a (similar) spec!

Comments are welcome
Henning Weddig
DK5LV

Am 15.08.2018 um 02:37 schrieb Nick VK4PP:
Hi Allison/ Kees/ Glenn/ other technical competent hams...

Would you consider working on a uBitx v2 so to speak, advice, criticisms and such?
Tweaking the current design as much as possible to perform better, address the major issues (spurs + harmonics)? 
Better components (2n2222a) ect,
Extra driver stage?
LPF layout..
proper BPF using QRP Labs Modules..

I would like to make it very modular, so its easy to fix/upgrade a section.
I will make some boards, happy to send to you for testing and evaluation at no cost.
Also smaller boars fit in a DL envelope (110x220mm) for DX shipping at $3.50. so that kind of defines the foot print.
Would be cool, 4 boards each about 105x105mm Stacking on one another.
Nano socketed on one board, SI5153 integrated, either SMT or Adafruit module ($$$ vs convenience)

I am not aiming to build a cheap copy, just an upgraded uBitx that you can assemble your self if you don't mind spending a bit more.

I want to enjoy the process and the radio, learn stuff along the way, contribute to the community.
As soon as this is no longer happening, there is no point in carrying on for me.

What are your thoughts people?

Cheers & 73.
Nick VK4PP 


Jack, W8TEE
 

Arv:

Agree, some are specialists in specific areas and there's no reason not to exploit that. However, you are also correct that there has to be a coordinated effort on the comm link between modules. When I was teaching, I had a sign on my desk:

    God so loved the world He didn't send a committee

Whoever's on the interface committee, it needs to be as small as possible. Otherwise, it's hard to get stuff done.

Jack, W8TEE


On Wednesday, August 15, 2018, 1:21:58 PM EDT, Arv Evans <arvid.evans@...> wrote:


The idea of a "Modular uBITX" is interesting because with a full set of specs for each
module it might be possible for different persons or groups to concentrate on one module,
resulting in a group-designed transceiver.  This has potential to reduce design work from
"doing it all" to doing just a module that could be incorporated into the overall product.
But modular does imply added electrical and mechanical specifications for interfaces,
which could be either good or bad.

Arv
_._


On Wed, Aug 15, 2018 at 2:57 AM Gordon Gibby <ggibby@...> wrote:
Those are great ideas, but what about a limitation on cost? Should be under $140.


On Aug 15, 2018, at 04:42, Henning Weddig via Groups.Io <hweddig@...> wrote:

Nick,

I already started to do "my" improvement on the µBITX, but then stopped, after reading and trying to understand all the issues involved and going back to ideas about a spec and blocks to be designed.

As I am an retired electrical engineer specialized in RF and communication techology (I started my profesional career in 1980 at the company Hagenuk in Kiel Germany designing part of the ship´s main communication receiver RX 1001 and later RX1001M, then working on the RF part of the ST900 cordless telephone) 

As I posess a "good equipped home lab" witrh used commercial equipment (spectrum analysers, networt analyser, signal generators and so on), I can test my disgins properl.

Before going to design something  we first should think about a specifiaction and wirte it down. Yes I know seldom engineers like it,  but this will give some insight into what has to be designed. Very important are also level diagrammes of the bolocks involved to see if the to be designed unit will fulfill the desired spec.

From this point of view Glenn´s way of doing a new design in  first to test sub modules is a brilliant idea as it was also used in the industry (and my last occupation within a physics high energy research lab). We often only developed a single unit wioth the use of connectorized "Mini Circuit modules" and built into a case.

As SMD compoents are used the size of the "cheap" chinese pcb´s should be < 100 * 100 mm.

I believe that this forum including Farhan can and shuld be a good potential for an optimized new µBITX!

My previous ideas:

modular design on pcb´s (<100 * 100 mm)

frequency range 10 kHz to 30 MHz

first IF > 45 MHz (to avoid the 2*IF - LO problem) using four pole xtal filters  e.g. 70 MHz (if easily avaliable)? Another "popular IF could be 58 MHz or 58.1125 MHz (used in Hagenuks cordless phones) My be enough NOS filters are laying around.

1) receiver/exciter pcb

2) xtal filter board for the second IF (e.g. 5 MHz) with filters for SSB; AM; FM(?), CW

2) input lowpass filter (corner freq. 1.6 MHz) plus  overlapping bandpass filters (e.g. 1.6 - 4MHz; 4 - 8 MHz, 8 - 16 MHz; 16 - 30 MHz)

3) driver board

5) PA board

6) lpf´s

7) VSWR bridge

8) VFO (several SI5351 ? to avoid crosstalk between outputs of a single SI5351 driven from a single reference (TCXO; or VCXO which could be synchronized to a GPS reference?)

RF signals to be routed via SMA connectors

Of course AGC should be inclueded!

For the mic amp I remember that for maritime ship transmitters there is a requirement to limiting the max RF output via a Mic compressor. Chips like the SSM2167 could easily fulfill such a (similar) spec!

Comments are welcome
Henning Weddig
DK5LV

Am 15.08.2018 um 02:37 schrieb Nick VK4PP:
Hi Allison/ Kees/ Glenn/ other technical competent hams...

Would you consider working on a uBitx v2 so to speak, advice, criticisms and such?
Tweaking the current design as much as possible to perform better, address the major issues (spurs + harmonics)? 
Better components (2n2222a) ect,
Extra driver stage?
LPF layout..
proper BPF using QRP Labs Modules..

I would like to make it very modular, so its easy to fix/upgrade a section.
I will make some boards, happy to send to you for testing and evaluation at no cost.
Also smaller boars fit in a DL envelope (110x220mm) for DX shipping at $3.50. so that kind of defines the foot print.
Would be cool, 4 boards each about 105x105mm Stacking on one another.
Nano socketed on one board, SI5153 integrated, either SMT or Adafruit module ($$$ vs convenience)

I am not aiming to build a cheap copy, just an upgraded uBitx that you can assemble your self if you don't mind spending a bit more.

I want to enjoy the process and the radio, learn stuff along the way, contribute to the community.
As soon as this is no longer happening, there is no point in carrying on for me.

What are your thoughts people?

Cheers & 73.
Nick VK4PP 


ajparent1/KB1GMX
 

Jack,

As to interfaces... RF or Data?  For dat Elecraft in the K2 took the approach that 
MPU is cheap so use a Bus to command them and identify what features exist.

I'm thinking the through hole Atmega328P chip.  (or Arduino Pro-mini)

Give me two wires and I can control the world, muh ha ha. ;)

Allison

Jack, W8TEE
 

As a programmer, data makes more sense to me and wouldn't that be simpler?  The Mega Pro Mini has a bunch of pins, but is pretty slow. The 328P doesn't have the I/O I'd need. Also, look at what you can do with a CAT command structure.

Jack, W8TEE


On Wednesday, August 15, 2018, 2:00:41 PM EDT, ajparent1/KB1GMX <kb1gmx@...> wrote:


Jack,

As to interfaces... RF or Data?  For dat Elecraft in the K2 took the approach that 
MPU is cheap so use a Bus to command them and identify what features exist.

I'm thinking the through hole Atmega328P chip.  (or Arduino Pro-mini)

Give me two wires and I can control the world, muh ha ha. ;)

Allison

VE3KRL
 

Hi,

I am not an expert in RF so I may be off on some assumptions, but I thought I put my nickle in (Canada doesn't use pennies so I don't have 2 cents)

With multiple boards I see a few options:
1) Stack them like an Arduino or QRPLab U3S
2) Lay them flat and join them like a jigsaw puzzle
3) Use the bus plane model like a PC computer

1) have RF on one edge, power on another, and digital with analog on a third edge to minimize cross talk. Upside is small and compact and can be scaled to matched what the operator wants to add. Downside is RF could radiate from one board to another and cause a bunch of other problems.

2) All the connectors on one edge. Upside is the boards are more space apart and wont cross talk as much, only slight mod to ubitx cases to hold the different boards. Downside the boards can be places in the wrong order.

3) Using edge connection and stand the boards on their edge, tap into the bus for the connections that are needed for the card. Upside cards can be placed in any order and just tap off the bus the needed signals for the board so can be more flexible in the placement of the boards. Downside maybe a RF nightmare on the bus with cross talk and if more boards are wanted to be added later a new bus board would need to be made and also the size might out grow the standard ubitx cases.

Keith VE3KRL

Arv Evans
 

Jack

I think we both have worked on large projects where there was an oversight group that
managed general product design and a number of other groups that designed parts for
that big picture effort.  This then raises the question of who will provide the oversight or
total package management to insure that (1) all modules work together, (2) all the groups
work together, and (3) infighting between groups is kept to a minimum.   8-)
In order to make this work it may have to be taken to a private mailing list for each group
in order to keep marginally interested parties from interfering with focus and productivity.

Arv
_._


On Wed, Aug 15, 2018 at 11:28 AM Jack Purdum via Groups.Io <jjpurdum=yahoo.com@groups.io> wrote:
Arv:

Agree, some are specialists in specific areas and there's no reason not to exploit that. However, you are also correct that there has to be a coordinated effort on the comm link between modules. When I was teaching, I had a sign on my desk:

    God so loved the world He didn't send a committee

Whoever's on the interface committee, it needs to be as small as possible. Otherwise, it's hard to get stuff done.

Jack, W8TEE


On Wednesday, August 15, 2018, 1:21:58 PM EDT, Arv Evans <arvid.evans@...> wrote:


The idea of a "Modular uBITX" is interesting because with a full set of specs for each
module it might be possible for different persons or groups to concentrate on one module,
resulting in a group-designed transceiver.  This has potential to reduce design work from
"doing it all" to doing just a module that could be incorporated into the overall product.
But modular does imply added electrical and mechanical specifications for interfaces,
which could be either good or bad.

Arv
_._


On Wed, Aug 15, 2018 at 2:57 AM Gordon Gibby <ggibby@...> wrote:
Those are great ideas, but what about a limitation on cost? Should be under $140.


On Aug 15, 2018, at 04:42, Henning Weddig via Groups.Io <hweddig@...> wrote:

Nick,

I already started to do "my" improvement on the µBITX, but then stopped, after reading and trying to understand all the issues involved and going back to ideas about a spec and blocks to be designed.

As I am an retired electrical engineer specialized in RF and communication techology (I started my profesional career in 1980 at the company Hagenuk in Kiel Germany designing part of the ship´s main communication receiver RX 1001 and later RX1001M, then working on the RF part of the ST900 cordless telephone) 

As I posess a "good equipped home lab" witrh used commercial equipment (spectrum analysers, networt analyser, signal generators and so on), I can test my disgins properl.

Before going to design something  we first should think about a specifiaction and wirte it down. Yes I know seldom engineers like it,  but this will give some insight into what has to be designed. Very important are also level diagrammes of the bolocks involved to see if the to be designed unit will fulfill the desired spec.

From this point of view Glenn´s way of doing a new design in  first to test sub modules is a brilliant idea as it was also used in the industry (and my last occupation within a physics high energy research lab). We often only developed a single unit wioth the use of connectorized "Mini Circuit modules" and built into a case.

As SMD compoents are used the size of the "cheap" chinese pcb´s should be < 100 * 100 mm.

I believe that this forum including Farhan can and shuld be a good potential for an optimized new µBITX!

My previous ideas:

modular design on pcb´s (<100 * 100 mm)

frequency range 10 kHz to 30 MHz

first IF > 45 MHz (to avoid the 2*IF - LO problem) using four pole xtal filters  e.g. 70 MHz (if easily avaliable)? Another "popular IF could be 58 MHz or 58.1125 MHz (used in Hagenuks cordless phones) My be enough NOS filters are laying around.

1) receiver/exciter pcb

2) xtal filter board for the second IF (e.g. 5 MHz) with filters for SSB; AM; FM(?), CW

2) input lowpass filter (corner freq. 1.6 MHz) plus  overlapping bandpass filters (e.g. 1.6 - 4MHz; 4 - 8 MHz, 8 - 16 MHz; 16 - 30 MHz)

3) driver board

5) PA board

6) lpf´s

7) VSWR bridge

8) VFO (several SI5351 ? to avoid crosstalk between outputs of a single SI5351 driven from a single reference (TCXO; or VCXO which could be synchronized to a GPS reference?)

RF signals to be routed via SMA connectors

Of course AGC should be inclueded!

For the mic amp I remember that for maritime ship transmitters there is a requirement to limiting the max RF output via a Mic compressor. Chips like the SSM2167 could easily fulfill such a (similar) spec!

Comments are welcome
Henning Weddig
DK5LV

Am 15.08.2018 um 02:37 schrieb Nick VK4PP:
Hi Allison/ Kees/ Glenn/ other technical competent hams...

Would you consider working on a uBitx v2 so to speak, advice, criticisms and such?
Tweaking the current design as much as possible to perform better, address the major issues (spurs + harmonics)? 
Better components (2n2222a) ect,
Extra driver stage?
LPF layout..
proper BPF using QRP Labs Modules..

I would like to make it very modular, so its easy to fix/upgrade a section.
I will make some boards, happy to send to you for testing and evaluation at no cost.
Also smaller boars fit in a DL envelope (110x220mm) for DX shipping at $3.50. so that kind of defines the foot print.
Would be cool, 4 boards each about 105x105mm Stacking on one another.
Nano socketed on one board, SI5153 integrated, either SMT or Adafruit module ($$$ vs convenience)

I am not aiming to build a cheap copy, just an upgraded uBitx that you can assemble your self if you don't mind spending a bit more.

I want to enjoy the process and the radio, learn stuff along the way, contribute to the community.
As soon as this is no longer happening, there is no point in carrying on for me.

What are your thoughts people?

Cheers & 73.
Nick VK4PP 


ajparent1/KB1GMX
 

Jack,

That was not a single processor thing.  The idea was a smart front panel I remember one really slick one. ;)
The Cat is external to a PC or tablet and not an internal bus for housekeeping and control.

That main user interface and control would drive a serial bus to internal mpus to do things like select filters,
measure SWR, aka dumb slow stuff.   The logic is a few wires simple bus protocol and simpler interconnect
as two wires (and ground) are easy to route.  I've done this in distributed control and sense systems.

Allison

Jack, W8TEE
 

I'd be happy to serve on such a committee, in a software capacity since I'm not much good on the EE stuff. It would have to be kept private to get anything done. Public emails could be used if an opinion is sought, but public would produce too much smoke I fear. Someone would both EE and software skills would  have the chair the group. I know someone who would be a great addition, mainly because he builds everything in modules. I want to talk to him before I say anything, however.

Jack, W8TEE


On Wednesday, August 15, 2018, 3:10:24 PM EDT, Arv Evans <arvid.evans@...> wrote:


Jack

I think we both have worked on large projects where there was an oversight group that
managed general product design and a number of other groups that designed parts for
that big picture effort.  This then raises the question of who will provide the oversight or
total package management to insure that (1) all modules work together, (2) all the groups
work together, and (3) infighting between groups is kept to a minimum.   8-)
In order to make this work it may have to be taken to a private mailing list for each group
in order to keep marginally interested parties from interfering with focus and productivity.

Arv
_._


On Wed, Aug 15, 2018 at 11:28 AM Jack Purdum via Groups.Io <jjpurdum=yahoo.com@groups.io> wrote:
Arv:

Agree, some are specialists in specific areas and there's no reason not to exploit that. However, you are also correct that there has to be a coordinated effort on the comm link between modules. When I was teaching, I had a sign on my desk:

    God so loved the world He didn't send a committee

Whoever's on the interface committee, it needs to be as small as possible. Otherwise, it's hard to get stuff done.

Jack, W8TEE


On Wednesday, August 15, 2018, 1:21:58 PM EDT, Arv Evans <arvid.evans@...> wrote:


The idea of a "Modular uBITX" is interesting because with a full set of specs for each
module it might be possible for different persons or groups to concentrate on one module,
resulting in a group-designed transceiver.  This has potential to reduce design work from
"doing it all" to doing just a module that could be incorporated into the overall product.
But modular does imply added electrical and mechanical specifications for interfaces,
which could be either good or bad.

Arv
_._


On Wed, Aug 15, 2018 at 2:57 AM Gordon Gibby <ggibby@...> wrote:
Those are great ideas, but what about a limitation on cost? Should be under $140.


On Aug 15, 2018, at 04:42, Henning Weddig via Groups.Io <hweddig@...> wrote:

Nick,

I already started to do "my" improvement on the µBITX, but then stopped, after reading and trying to understand all the issues involved and going back to ideas about a spec and blocks to be designed.

As I am an retired electrical engineer specialized in RF and communication techology (I started my profesional career in 1980 at the company Hagenuk in Kiel Germany designing part of the ship´s main communication receiver RX 1001 and later RX1001M, then working on the RF part of the ST900 cordless telephone) 

As I posess a "good equipped home lab" witrh used commercial equipment (spectrum analysers, networt analyser, signal generators and so on), I can test my disgins properl.

Before going to design something  we first should think about a specifiaction and wirte it down. Yes I know seldom engineers like it,  but this will give some insight into what has to be designed. Very important are also level diagrammes of the bolocks involved to see if the to be designed unit will fulfill the desired spec.

From this point of view Glenn´s way of doing a new design in  first to test sub modules is a brilliant idea as it was also used in the industry (and my last occupation within a physics high energy research lab). We often only developed a single unit wioth the use of connectorized "Mini Circuit modules" and built into a case.

As SMD compoents are used the size of the "cheap" chinese pcb´s should be < 100 * 100 mm.

I believe that this forum including Farhan can and shuld be a good potential for an optimized new µBITX!

My previous ideas:

modular design on pcb´s (<100 * 100 mm)

frequency range 10 kHz to 30 MHz

first IF > 45 MHz (to avoid the 2*IF - LO problem) using four pole xtal filters  e.g. 70 MHz (if easily avaliable)? Another "popular IF could be 58 MHz or 58.1125 MHz (used in Hagenuks cordless phones) My be enough NOS filters are laying around.

1) receiver/exciter pcb

2) xtal filter board for the second IF (e.g. 5 MHz) with filters for SSB; AM; FM(?), CW

2) input lowpass filter (corner freq. 1.6 MHz) plus  overlapping bandpass filters (e.g. 1.6 - 4MHz; 4 - 8 MHz, 8 - 16 MHz; 16 - 30 MHz)

3) driver board

5) PA board

6) lpf´s

7) VSWR bridge

8) VFO (several SI5351 ? to avoid crosstalk between outputs of a single SI5351 driven from a single reference (TCXO; or VCXO which could be synchronized to a GPS reference?)

RF signals to be routed via SMA connectors

Of course AGC should be inclueded!

For the mic amp I remember that for maritime ship transmitters there is a requirement to limiting the max RF output via a Mic compressor. Chips like the SSM2167 could easily fulfill such a (similar) spec!

Comments are welcome
Henning Weddig
DK5LV

Am 15.08.2018 um 02:37 schrieb Nick VK4PP:
Hi Allison/ Kees/ Glenn/ other technical competent hams...

Would you consider working on a uBitx v2 so to speak, advice, criticisms and such?
Tweaking the current design as much as possible to perform better, address the major issues (spurs + harmonics)? 
Better components (2n2222a) ect,
Extra driver stage?
LPF layout..
proper BPF using QRP Labs Modules..

I would like to make it very modular, so its easy to fix/upgrade a section.
I will make some boards, happy to send to you for testing and evaluation at no cost.
Also smaller boars fit in a DL envelope (110x220mm) for DX shipping at $3.50. so that kind of defines the foot print.
Would be cool, 4 boards each about 105x105mm Stacking on one another.
Nano socketed on one board, SI5153 integrated, either SMT or Adafruit module ($$$ vs convenience)

I am not aiming to build a cheap copy, just an upgraded uBitx that you can assemble your self if you don't mind spending a bit more.

I want to enjoy the process and the radio, learn stuff along the way, contribute to the community.
As soon as this is no longer happening, there is no point in carrying on for me.

What are your thoughts people?

Cheers & 73.
Nick VK4PP 


Jack, W8TEE
 

No, I didn't mean to suggest that CAT be used for internal control. I was just pointing out that control is possible with messaging. There are existing bus protocols (e.g., SPI, I2C, CAN) and many µC's provide for them, but I don't know enough to judge whether they would be useful here.

Jack, W8TEE

On Wednesday, August 15, 2018, 3:52:57 PM EDT, ajparent1/KB1GMX <kb1gmx@...> wrote:


Jack,

That was not a single processor thing.  The idea was a smart front panel I remember one really slick one. ;)
The Cat is external to a PC or tablet and not an internal bus for housekeeping and control.

That main user interface and control would drive a serial bus to internal mpus to do things like select filters,
measure SWR, aka dumb slow stuff.   The logic is a few wires simple bus protocol and simpler interconnect
as two wires (and ground) are easy to route.  I've done this in distributed control and sense systems.

Allison

Tom, wb6b
 

If we are upping the processing power on-board, why don't we build a Soft Rock type of transceiver with all bands, relay switched filters and 10 watts out?

Using the onboard processor instead of an external laptop or PC for the signal processing.

Tom, wb6b

Jack, W8TEE
 

That's why we picked the Teensy 3.6.

Jack, W8TEE


On Wednesday, August 15, 2018, 4:54:56 PM EDT, Tom, wb6b <wb6b@...> wrote:


If we are upping the processing power on-board, why don't we build a Soft Rock type of transceiver with all bands, relay switched filters and 10 watts out?

Using the onboard processor instead of an external laptop or PC for the signal processing.

Tom, wb6b

Gwen Patton
 

I have a Softrock-based SDR that still makes use of a sound module connection to my PC for processing. It costs $100 more than the uBitX without an enclosure. It's similar in that it comes with the board fully populated, requiring just final assembly. It's a nice rig with LOTS of features, but it can be cumbersome because it needs a PC to complete it. I like the thing, but I wanted to build something I could easily take into the field without having to lug a PC with me to make it work. Hence the uBitX.

https://www.hobbypcb.com/rs-hfiq

73,
Gwen NG3P

Alan de G1FXB
 

Hi Tom,

something like?

http://www.sdr-cube.com/


Alan


On 15/08/2018 21:54, Tom, wb6b wrote:
If we are upping the processing power on-board, why don't we build a Soft Rock type of transceiver with all bands, relay switched filters and 10 watts out?

Using the onboard processor instead of an external laptop or PC for the signal processing.

Tom, wb6b

Diane Bruce
 

On Wed, Aug 15, 2018 at 01:54:43PM -0700, Tom, wb6b wrote:
If we are upping the processing power on-board, why don't we build a Soft Rock type of transceiver with all bands, relay switched filters and 10 watts out?

Using the onboard processor instead of an external laptop or PC for the signal processing.
Why not indeed. Like the M0NKA-mcHF ?

Tom, wb6b
Diane, va3db


--
- db@... db@... http://www.db.net/~db

Roy Appleton
 

On Wed, Aug 15, 2018, 3:54 PM Tom, wb6b <wb6b@...> wrote:
If we are upping the processing power on-board, why don't we build a Soft Rock type of transceiver with all bands, relay switched filters and 10 watts out?

Using the onboard processor instead of an external laptop or PC for the signal processing.

Tom, wb6b

Gary Anderson
 

Or like this one!
https://ae5x.blogspot.com/2017/12/10-80-meter-ssbcw-transceiver-for-119.html

That's how I ended up here.
Gary
AG5TX

Dr. Flywheel
 

By utilizing a Teensy 3.6 board you are opening the way for DSP-based generation and reconstruction of SSB and other signals. For example a pair of 45 deg. symmetrical Hilbert transforms can take care of precise phasing to effectively suppress the carrier and unwanted sideband. Such Hilbert filter can simultaneously replace the second IF crystal filter, if the conversion is brought down to audio frequencies. Being a programmable filter, the Hilbert transform can also provide variable bandwidth for the desired mode of operation. Further audio processing, like the audio band equalizer that you apparently implemented is just as icing on the cake. With appropriate CODEC, the Teensy 3.6 with its DMA capabilities, can easily support 192 kHz sampling rate, which means that in principle you could show FFT an waterfall diagrams in real time for a much wider bandwidth. This becomes essentially a hybrid SDR architecture at a very low cost.

--Ron   N7FTZ   

On Wed, Aug 15, 2018 at 10:19 AM Jack Purdum via Groups.Io <jjpurdum=yahoo.com@groups.io> wrote:
Carl:

Some very good ideas.

I'm showing the Rev 2 JackAl board here, partly to show what we done, but also to show the mistakes we made along the way. (We're doing
the Rev 4 board now.) First, we've taken the buck converter off simply because it was too fragile when adjusting...far to easy to rip the adjusting screw right off the board. Second, the 7W audio amplifier (big IC on lower left) is stupid for the nano acres it takes plus its cost. Most users have powered speakers or can easily add them. We don't have a direct I2C connection, but we do have an SPI interface for the touch screen display. (Our display handles the video processing.) The rest are connections that work through the exiting µBITX headers, which would not be the same for a new design. Still, the above is less than 100mm x 100mm and parts are being taken off. Obviously, we have the Si5351 chip onboard, but that probably should be on the main board. The SMD parts will be part of the PCB when sold.

To me, perhaps the most important thing we've done is bring out a bunch of pins, both digital and analog, for others to use. I hope the selected processor for such a project has a bunch available.

Jack, W8TEE



On Wednesday, August 15, 2018, 12:27:03 PM EDT, RCBoatGuy via Groups.Io <ijnfan-HamRadio=yahoo.com@groups.io> wrote:


Here's some features I'd like to see in any new design that shouldn't cost much, but would make life/testing/experimentation easier:

- Sockets for CPU boards on any new Raduino design.  (Teensyduino has this already, and I think the JackAl does, too)

- Sockets for relays, as these have been a frequent source of failure

- Move any pull-up resistors required onto the Raduino/Teensyduino/JackAl board and not rely on the user to wire them up.  Many users either failed to wire up the 4.7K external resistor correctly or had the connection fail later, causing the rig to immediately go into transmit on power-up.  This is easily avoided by having the required pull-ups on the Raduino/Teensyduino/JackAl board itself.

- Add 3-pin 0.1" input and output headers/jumpers to each section (Bi-di Amps, Audio Amp, Mic Amp, BPF, PA, LPF, etc) on a given board so that the given section can be isolated and tested independently.  For inputs to a section, 1st pin is output from prior section, 2nd pin is input to current section, 3rd pin is GND.   For outputs from a section, 1st pin is output from section, 2nd pin is input to next section, 3rd pin is GND.  Normal operation uses shorting jumpers across pins 1 and 2 to allow signals to flow thru, but jumpers can be removed and test inputs/outputs connected via molex/etc connectors to pins 2 and 3 (or to all 3 pins if desired).  This also makes it easier to replace a given section with an external circuit for experimentation/modification.

- Room for extra I2C headers on the Raduino (Teensyduino already has this, not sure about the JackAl) that the user can install later if desired

- Would be nice if the modular design had the PA on a separate board so different PAs can be used based on user preference.  Having different boards for a IRF510 PA, a RD16HHF1 PA, etc, would be nice as the user can pick and choose what they want, or build their own much easier.

- Support for adding additional BPF/LPF for those that want 160M, 6M, etc

- As for the LPF relays, I'd recommend using a relay scheme like that on the mcHF transceiver.  Their approach minimized the number of relays (only 4 DPDT relays needed for 4 filters), but still had filter inputs and filter outputs going to different relays.

- Design board so that the Raduino/Teensyduino/JackAl board has no obstructions from parts and/or connectors along the entire edge of the radio board.  The Teensyduino had to design in special cut-outs to use with the current uBitX due to obstructions. It would be nice if cut-outs like this were not needed in the future.

- Si5351 on main board, not on Raduino/Teensyduino/JackAl

That's my 2 cents.  Take it for what it's worth.  :)

73, 

Carl, K0MWC

Jerry Gaffke
 

Very cool, I may well bite on that qsx40.

But the *Bitx* rigs scratch an itch.
There's a need for a simple back-to-basics almost-all-analog radio
you can poke a scope probe into. 
Educational, for one, not many of us will figure out the DSP code of an SDR rig
to where we can take significant whacks at it. 
And an analog rig can sound better.

Jerry


On Wed, Aug 15, 2018 at 02:44 PM, Roy Appleton wrote:
Or like this one!
 
 

Eddie Esserman
 

Mr. Farhan,

We could sure use more that attitude these days! Your open architecture about the radio extends to your person!

I'm in for a new one, to play again.  These are a hoot, and I've been away since before chips, much less computers in radios.  My other rig is a KWM2.

Eddie