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mono band 2 meters rig based on the micro BITx circuit #ubitx #2meters

 

there are just a few challenges and many ways to meet them in transiting to 435 MHz, VHF is just a milestone along the way. The idea of making something on VHF/UHF is no longer economically justified if you are doing it just to save money. You can buy a baofeng for twenty dollars. Probably, it is a good idea to do that in anycase, you will have a ready rig to test your homebrew with.

The local oscillator:
The first challenge is to get a local oscillator going at around 400 MHz. There are three ways to do it:
- A crystal oscillator with a multiplier chain. This needs you to have a good way to sniff RF frequencies. A wavemeter of a lecher line would do the trick.
- Just triple the Si5351. This means, you need to tune just one bandpass filter at 435 MHz
- Use an Si589 or Si570, LVDS version. This costs as much as a Baofeng, you can order it from Mouser.

Architecture: The options are:
- Two diode mixers that directly mix down to audio, to make a phasing, direct conversion transceiver. This is simple, it involves cutting a phase line down by millimeters until you get the phase angle right. But you don't dabble with all the fun (really??) of a superhet.
- Single conversion to 20-25 MHz IF with stripline filters to keep the image rejection high, it is a bitx from the other side
- double conversion to 45 MHz, this throws the image to around 350 MHz, easily suppressed by LC bandpass filters.

Modulation/Demodulation:
There are many ways to achieve it. You can build analog mod/demod with conventional technology as done in the bitx transceivers. Or...
add an SDR back-end (if you are lazy).

What do you guys think?

- f

On Saturday 28 April 2018 08:32 AM, Tim Gorman wrote:
Respectfully, as Allison points out, it's not just the PA active element
that will be the problem. When your frequency width is an order of
magnitude, e.g. 14Mhz to 144Mhz, you begin to run into all kinds of
issues with components. Lead lengths and circuit trace lengths/widths
at 2m cause many more problems than at 14Mhz. It gets even worse at
432Mhz.

I agree with others on here. It would be a lot more feasible to do one
band modules, e.g. one for 2m and another one for 432Mhz, that are
small enough they could be placed in one case along with a ubitx
being used as an IF amplifier.

tim ab0wr

On Sat, 28 Apr 2018 01:12:16 +0000
"Ashhar Farhan" <farhanbox@...> wrote:

Allison,
For a power chain of about 5 watts that goes from 50 mhz to 500 mhz,
what would be your recommendations? The RD15HVF1 seems to be used
frequently at 435 Mhz. Are there any broadband alternatives? What
kind of cores can we use at UHF?
- f

On Sat, 28 Apr 2018, 06:37 ajparent1/KB1GMX, <kb1gmx@...> wrote:

Several things, like others have repeatedly pointed out the uBITX
is very unsuited for FM or AM.
FM needs wider filter and far more gain to get the needed limiting
action. Its not drop in its full
replacement. A Baofeng UV5R goes for 30 bucks and does 2M and
70CM. AM there are
issues with drive level and sustained power out, that and its
sparsely used. My opinion is
that if you want all that get a FT817, its a do all and has a noise
blanker.

To get the front end to cover VHF the LO system deliver a VHF LO
(95mhz for 6M, about 99 or 189mhz for 2m)
and the input filter needs to pass the VHF band and not a low
pass. IF memory sers the 5351 can go to 220Mhz
A LNA before the mixer would be required for reasonable performance.
For UHF if you had a version of the
5351 or maybe used a si570 flavor to generate the LO and an
improved mixer 432 is possible but its more
effort and would likely need a board redesign.

UHF is better done with a competent converter/transverter with a
404mhz LO and run that into a uBitx at 28mhz.

In all cases 6 though 70cm the tx power chain would need work as the
drivers are all 300mhz FT devices
just will not do it. The IRF510 I've used at 50mhz as a monoband
linear and its respectable
(40+W for push pull @ 28V properly done for 6M only) but I think
maybe 70mhz is a stretch without
first trying. In all cases the TX chain is mono band only as VHF
impedance matching from stage
to stage is required. Just dropping in higher FT devices will not
help its a across the board redesign
for a specific band.

Receiving is easy enough, transmit above 50mhz is going to be
harder.


Allison
 

I would add that Si5351 could be directly to drive a harmonic mixer. A harmonic diode mixer is singly balanced mixer (like the one in the bitx transceivers) except that there is an additional pair of diodes strapped across each of the two diodes. So, the mixer turns on on the high positive peak of the oscillator as well as the lowest negative peak of the oscillator, in effect it turns on twice for every oscillator cycle. this would reduce the requirement to just your regular radiuno driving 1N5711 or 1N4148 diodes in the mixer. The big question is, what core do we use for these mixers? Should be mangle an ADE-1 to get at its transformers? Allison, can you help?

- f

On Saturday 28 April 2018 10:43 AM, Ashhar Farhan wrote:
there are just a few challenges and many ways to meet them in transiting to 435 MHz, VHF is just a milestone along the way. The idea of making something on VHF/UHF is no longer economically justified if you are doing it just to save money. You can buy a baofeng for twenty dollars. Probably, it is a good idea to do that in anycase, you will have a ready rig to test your homebrew with.

The local oscillator:
The first challenge is to get a local oscillator going at around 400 MHz. There are three ways to do it:
- A crystal oscillator with a multiplier chain. This needs you to have a good way to sniff RF frequencies. A wavemeter of a lecher line would do the trick.
- Just triple the Si5351. This means, you need to tune just one bandpass filter at 435 MHz
- Use an Si589 or Si570, LVDS version. This costs as much as a Baofeng, you can order it from Mouser.

Architecture: The options are:
- Two diode mixers that directly mix down to audio, to make a phasing, direct conversion transceiver. This is simple, it involves cutting a phase line down by millimeters until you get the phase angle right. But you don't dabble with all the fun (really??) of a superhet.
- Single conversion to 20-25 MHz IF with stripline filters to keep the image rejection high, it is a bitx from the other side
- double conversion to 45 MHz, this throws the image to around 350 MHz, easily suppressed by LC bandpass filters.

Modulation/Demodulation:
There are many ways to achieve it. You can build analog mod/demod with conventional technology as done in the bitx transceivers. Or...
add an SDR back-end (if you are lazy).

What do you guys think?

- f




On Saturday 28 April 2018 08:32 AM, Tim Gorman wrote:
Respectfully, as Allison points out, it's not just the PA active element
that will be the problem. When your frequency width is an order of
magnitude, e.g. 14Mhz to 144Mhz, you begin to run into all kinds of
issues with components. Lead lengths and circuit trace lengths/widths
at 2m cause many more problems than at 14Mhz. It gets even worse at
432Mhz.

I agree with others on here. It would be a lot more feasible to do one
band modules, e.g. one for 2m and another one for 432Mhz, that are
small enough they could be placed in one case along with a ubitx
being used as an IF amplifier.

tim ab0wr

On Sat, 28 Apr 2018 01:12:16 +0000
"Ashhar Farhan" <farhanbox@...> wrote:

Allison,
For a power chain of about 5 watts that goes from 50 mhz to 500 mhz,
what would be your recommendations? The RD15HVF1 seems to be used
frequently at 435 Mhz. Are there any broadband alternatives? What
kind of cores can we use at UHF?
- f

On Sat, 28 Apr 2018, 06:37 ajparent1/KB1GMX, <kb1gmx@...> wrote:

Several things, like others have repeatedly pointed out the uBITX
is very unsuited for FM or AM.
FM needs wider filter and far more gain to get the needed limiting
action.? Its not drop in its full
replacement.? A Baofeng UV5R goes for 30 bucks and does 2M and
70CM.??? AM there are
issues with drive level and sustained power out, that and its
sparsely used.? My opinion is
that if you want all that get a FT817, its a do all and has a noise
blanker.

To get the front end to cover VHF the LO system deliver a VHF LO
(95mhz for 6M, about 99 or 189mhz for 2m)
and the input filter needs to pass the VHF band and not a low
pass.? IF memory sers the 5351 can go to 220Mhz
A LNA before the mixer would be required for reasonable performance.
For UHF if you had a version of the
5351 or maybe used a si570 flavor to generate the LO and an
improved mixer 432 is possible but its more
effort and would likely need a board redesign.

UHF is better done with a competent converter/transverter with a
404mhz LO and run that into a uBitx at 28mhz.

In all cases 6 though 70cm the tx power chain would need work as the
drivers are all 300mhz FT devices
just will not do it.?? The IRF510 I've used at 50mhz as a monoband
linear and its respectable
(40+W for push pull @ 28V properly done for 6M only) but I think
maybe 70mhz is a stretch without
first trying.? In all cases the TX chain is mono band only as VHF
impedance matching from stage
to stage is required. Just dropping in higher FT devices will not
help its a across the board redesign
for a specific band.

Receiving is easy enough, transmit above 50mhz is going to be
harder.


Allison
Rahul Srivastava
 

Hi !?

Getting cores for such high frequency is easy. Use one from cable TV splitters/ They work on VHF Band III and beyond.?

Rahul
 

I'm lost as to what your goal is here.
1. The baofeng won't do SSB. Are you wanting to build a SSB unit or an
FM unit?
2. Are you thinking of a handheld or a desktop?
3. a phase line at 432Mhz won't be correct for 144Mhz. Are you thinking
a two-band unit or one-band unit?

tim ab0wr



On Sat, 28 Apr 2018 10:43:31 +0530
"Ashhar Farhan" <farhanbox@...> wrote:

there are just a few challenges and many ways to meet them in
transiting to 435 MHz, VHF is just a milestone along the way. The
idea of making something on VHF/UHF is no longer economically
justified if you are doing it just to save money. You can buy a
baofeng for twenty dollars. Probably, it is a good idea to do that in
anycase, you will have a ready rig to test your homebrew with.

The local oscillator:
The first challenge is to get a local oscillator going at around 400
MHz. There are three ways to do it:
- A crystal oscillator with a multiplier chain. This needs you to
have a good way to sniff RF frequencies. A wavemeter of a lecher line
would do the trick.
- Just triple the Si5351. This means, you need to tune just one
bandpass filter at 435 MHz
- Use an Si589 or Si570, LVDS version. This costs as much as a
Baofeng, you can order it from Mouser.

Architecture: The options are:
- Two diode mixers that directly mix down to audio, to make a
phasing, direct conversion transceiver. This is simple, it involves
cutting a phase line down by millimeters until you get the phase
angle right. But you don't dabble with all the fun (really??) of a
superhet.
- Single conversion to 20-25 MHz IF with stripline filters to keep
the image rejection high, it is a bitx from the other side
- double conversion to 45 MHz, this throws the image to around 350
MHz, easily suppressed by LC bandpass filters.

Modulation/Demodulation:
There are many ways to achieve it. You can build analog mod/demod
with conventional technology as done in the bitx transceivers. Or...
add an SDR back-end (if you are lazy).

What do you guys think?

- f




On Saturday 28 April 2018 08:32 AM, Tim Gorman wrote:
Respectfully, as Allison points out, it's not just the PA active
element that will be the problem. When your frequency width is an
order of magnitude, e.g. 14Mhz to 144Mhz, you begin to run into all
kinds of issues with components. Lead lengths and circuit trace
lengths/widths at 2m cause many more problems than at 14Mhz. It
gets even worse at 432Mhz.

I agree with others on here. It would be a lot more feasible to do
one band modules, e.g. one for 2m and another one for 432Mhz, that
are small enough they could be placed in one case along with a ubitx
being used as an IF amplifier.

tim ab0wr

On Sat, 28 Apr 2018 01:12:16 +0000
"Ashhar Farhan" <farhanbox@...> wrote:

Allison,
For a power chain of about 5 watts that goes from 50 mhz to 500
mhz, what would be your recommendations? The RD15HVF1 seems to be
used frequently at 435 Mhz. Are there any broadband alternatives?
What kind of cores can we use at UHF?
- f

On Sat, 28 Apr 2018, 06:37 ajparent1/KB1GMX, <kb1gmx@...>
wrote:
Several things, like others have repeatedly pointed out the uBITX
is very unsuited for FM or AM.
FM needs wider filter and far more gain to get the needed limiting
action. Its not drop in its full
replacement. A Baofeng UV5R goes for 30 bucks and does 2M and
70CM. AM there are
issues with drive level and sustained power out, that and its
sparsely used. My opinion is
that if you want all that get a FT817, its a do all and has a
noise blanker.

To get the front end to cover VHF the LO system deliver a VHF LO
(95mhz for 6M, about 99 or 189mhz for 2m)
and the input filter needs to pass the VHF band and not a low
pass. IF memory sers the 5351 can go to 220Mhz
A LNA before the mixer would be required for reasonable
performance. For UHF if you had a version of the
5351 or maybe used a si570 flavor to generate the LO and an
improved mixer 432 is possible but its more
effort and would likely need a board redesign.

UHF is better done with a competent converter/transverter with a
404mhz LO and run that into a uBitx at 28mhz.

In all cases 6 though 70cm the tx power chain would need work as
the drivers are all 300mhz FT devices
just will not do it. The IRF510 I've used at 50mhz as a monoband
linear and its respectable
(40+W for push pull @ 28V properly done for 6M only) but I think
maybe 70mhz is a stretch without
first trying. In all cases the TX chain is mono band only as VHF
impedance matching from stage
to stage is required. Just dropping in higher FT devices will not
help its a across the board redesign
for a specific band.

Receiving is easy enough, transmit above 50mhz is going to be
harder.


Allison
 

Looks like the goal is to build something more challenging than the uBitx.
Beyond that what it is or does is totally up in the air.
Discussion seems to be moving toward a single band rig capable of SSB/CW about uBitx size.

A few thoughts of my own:
Phase noise from that si5351 gets worse as the freq goes up, maybe an si5338 or si5341?
Having all oscillators off a single reference makes calibration much easier.
Could be used for cross band ops if it receives on more bands than it transmits.
A wideband receiver could also be a spectrum analyzer, use digital techniques
on the audio when resolution better than the crystal filters is required.
Transmit mixer, drivers, final could be a separate board for each band desired,
zero transmit boards is an option for receive only.

Jerry


On Sat, Apr 28, 2018 at 05:55 am, Tim Gorman wrote:
I'm lost as to what your goal is here.
1. The baofeng won't do SSB. Are you wanting to build a SSB unit or an
FM unit?
2. Are you thinking of a handheld or a desktop?
3. a phase line at 432Mhz won't be correct for 144Mhz. Are you thinking
a two-band unit or one-band unit?
 

¿ªÔÆÌåÓý

If such a radio is just CW and SSB, those ultra-cheap transverters from the Ukraine are by far the best solution.? If the radio will operate FM¡­ that¡¯s where a redesign is required.

?

I¡¯m using one of the transverters now and they work fine with some simple interfacing.

?

?

Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ

?

Owner - Operator

Big Signal Ranch ¨C K9ZC

Staunton, Illinois

?

Owner ¨C Operator

Villa Grand Piton ¨C J68HZ

Soufriere, St. Lucia W.I.

Rent it:

Like us on Facebook!

?

Moderator ¨C North American QRO Group at Groups.IO.

?

email:? bill@...

?

?

From: [email protected] [mailto:[email protected]] On Behalf Of Jerry Gaffke via Groups.Io
Sent: Saturday, April 28, 2018 9:58 AM
To: [email protected]
Subject: Re: [BITX20] mono band 2 meters rig based on the micro BITx circuit #ubitx #2meters

?

Looks like the goal is to build something more challenging than the uBitx.
Beyond that what it is or does is totally up in the air.
Discussion seems to be moving toward a single band rig capable of SSB/CW about uBitx size.

A few thoughts of my own:
Phase noise from that si5351 gets worse as the freq goes up, maybe an si5338 or si5341?
Having all oscillators off a single reference makes calibration much easier.
Could be used for cross band ops if it receives on more bands than it transmits.
A wideband receiver could also be a spectrum analyzer, use digital techniques
on the audio when resolution better than the crystal filters is required.
Transmit mixer, drivers, final could be a separate board for each band desired,
zero transmit boards is an option for receive only.

Jerry


On Sat, Apr 28, 2018 at 05:55 am, Tim Gorman wrote:

I'm lost as to what your goal is here.
1. The baofeng won't do SSB. Are you wanting to build a SSB unit or an
FM unit?
2. Are you thinking of a handheld or a desktop?
3. a phase line at 432Mhz won't be correct for 144Mhz. Are you thinking
a two-band unit or one-band unit?


Virus-free.

 

Tim,
I was saying that 435 mhz is the real adventure. If you can crack 435 mhz, you can scale down to 144 mhz. I was mentioning the phasing line for 435 mhz.?
It should be multimode : fm, am, ssb, cw. That's a tall idea. But as josef conrad said, what redeems it is the idea.?
- f


On 28 Apr 2018 6:25 pm, "Tim Gorman" <tgorman2@...> wrote:
I'm lost as to what your goal is here.
1. The baofeng won't do SSB. Are you wanting to build a SSB unit or an
FM unit?
2. Are you thinking of a handheld or a desktop?
3. a phase line at 432Mhz won't be correct for 144Mhz. Are you thinking
a two-band unit or one-band unit?

tim ab0wr




On Sat, 28 Apr 2018 10:43:31 +0530
"Ashhar Farhan" <farhanbox@...> wrote:

> there are just a few challenges and many ways to meet them in
> transiting to 435 MHz, VHF is just a milestone along the way. The
> idea of making something on VHF/UHF is no longer economically
> justified if you are doing it just to save money. You can buy a
> baofeng for twenty dollars. Probably, it is a good idea to do that in
> anycase, you will have a ready rig to test your homebrew with.
>
> The local oscillator:
> The first challenge is to get a local oscillator going at around 400
> MHz. There are three ways to do it:
> - A crystal oscillator with a multiplier chain. This needs you to
> have a good way to sniff RF frequencies. A wavemeter of a lecher line
> would do the trick.
> - Just triple the Si5351. This means, you need to tune just one
> bandpass filter at 435 MHz
> - Use an Si589 or Si570, LVDS version. This costs as much as a
> Baofeng, you can order it from Mouser.
>
> Architecture: The options are:
> - Two diode mixers that directly mix down to audio, to make a
> phasing, direct conversion transceiver. This is simple, it involves
> cutting a phase line down by millimeters until you get the phase
> angle right. But you don't dabble with all the fun (really??) of a
> superhet.
> - Single conversion to 20-25 MHz IF with stripline filters to keep
> the image rejection high, it is a bitx from the other side
> - double conversion to 45 MHz, this throws the image to around 350
> MHz, easily suppressed by LC bandpass filters.
>
> Modulation/Demodulation:
> There are many ways to achieve it. You can build analog mod/demod
> with conventional technology as done in the bitx transceivers. Or...
> add an SDR back-end (if you are lazy).
>
> What do you guys think?
>
> - f
>
>
>
>
> On Saturday 28 April 2018 08:32 AM, Tim Gorman wrote:
> > Respectfully, as Allison points out, it's not just the PA active
> > element that will be the problem. When your frequency width is an
> > order of magnitude, e.g. 14Mhz to 144Mhz, you begin to run into all
> > kinds of issues with components. Lead lengths and circuit trace
> > lengths/widths at 2m cause many more problems than at 14Mhz. It
> > gets even worse at 432Mhz.
> >
> > I agree with others on here. It would be a lot more feasible to do
> > one band modules, e.g. one for 2m and another one for 432Mhz, that
> > are small enough they could be placed in one case along with a ubitx
> > being used as an IF amplifier.
> >
> > tim ab0wr
> >
> > On Sat, 28 Apr 2018 01:12:16 +0000
> > "Ashhar Farhan" <farhanbox@...> wrote:
> >?
> >> Allison,
> >> For a power chain of about 5 watts that goes from 50 mhz to 500
> >> mhz, what would be your recommendations? The RD15HVF1 seems to be
> >> used frequently at 435 Mhz. Are there any broadband alternatives?
> >> What kind of cores can we use at UHF?
> >> - f
> >>
> >> On Sat, 28 Apr 2018, 06:37 ajparent1/KB1GMX, <kb1gmx@...>
> >> wrote:
> >>> Several things, like others have repeatedly pointed out the uBITX
> >>> is very unsuited for FM or AM.
> >>> FM needs wider filter and far more gain to get the needed limiting
> >>> action.? Its not drop in its full
> >>> replacement.? A Baofeng UV5R goes for 30 bucks and does 2M and
> >>> 70CM.? ? AM there are
> >>> issues with drive level and sustained power out, that and its
> >>> sparsely used.? My opinion is
> >>> that if you want all that get a FT817, its a do all and has a
> >>> noise blanker.
> >>>
> >>> To get the front end to cover VHF the LO system deliver a VHF LO
> >>> (95mhz for 6M, about 99 or 189mhz for 2m)
> >>> and the input filter needs to pass the VHF band and not a low
> >>> pass.? IF memory sers the 5351 can go to 220Mhz
> >>> A LNA before the mixer would be required for reasonable
> >>> performance. For UHF if you had a version of the
> >>> 5351 or maybe used a si570 flavor to generate the LO and an
> >>> improved mixer 432 is possible but its more
> >>> effort and would likely need a board redesign.
> >>>
> >>> UHF is better done with a competent converter/transverter with a
> >>> 404mhz LO and run that into a uBitx at 28mhz.
> >>>
> >>> In all cases 6 though 70cm the tx power chain would need work as
> >>> the drivers are all 300mhz FT devices
> >>> just will not do it.? ?The IRF510 I've used at 50mhz as a monoband
> >>> linear and its respectable
> >>> (40+W for push pull @ 28V properly done for 6M only) but I think
> >>> maybe 70mhz is a stretch without
> >>> first trying.? In all cases the TX chain is mono band only as VHF
> >>> impedance matching from stage
> >>> to stage is required. Just dropping in higher FT devices will not
> >>> help its a across the board redesign
> >>> for a specific band.
> >>>
> >>> Receiving is easy enough, transmit above 50mhz is going to be
> >>> harder.
> >>>
> >>>
> >>> Allison
> >>>
> >>>
> >>>
> >>>
> >>>? ? ?
> >
> >
> >?
>
>
>
>





Michael Kana
 

¿ªÔÆÌåÓý

Go with a transverter and use a 10 meter IF.?
I have seen dual band 2 meter/432 MHz transverters out of the Ukraine or options such as Elecraft. Down East Microwave also sold vhf and uhf transverters but I believe they spun that business off to another builder.?
Or find a used one on the auction site.?

I have picked up the complete Elecraft line 6, 2, 222, and 432 used except for the 222 I¡¯m building and driving with my Kx3 or dedicated 10 meter IF radio?
73
Mike AA9IL?

Warning! ?This is transmitted over a non secure medium

On Apr 28, 2018, at 9:57 AM, Jerry Gaffke via Groups.Io <jgaffke@...> wrote:

Looks like the goal is to build something more challenging than the uBitx.
Beyond that what it is or does is totally up in the air.
Discussion seems to be moving toward a single band rig capable of SSB/CW about uBitx size.

A few thoughts of my own:
Phase noise from that si5351 gets worse as the freq goes up, maybe an si5338 or si5341?
Having all oscillators off a single reference makes calibration much easier.
Could be used for cross band ops if it receives on more bands than it transmits.
A wideband receiver could also be a spectrum analyzer, use digital techniques
on the audio when resolution better than the crystal filters is required.
Transmit mixer, drivers, final could be a separate board for each band desired,
zero transmit boards is an option for receive only.

Jerry


On Sat, Apr 28, 2018 at 05:55 am, Tim Gorman wrote:
I'm lost as to what your goal is here.
1. The baofeng won't do SSB. Are you wanting to build a SSB unit or an
FM unit?
2. Are you thinking of a handheld or a desktop?
3. a phase line at 432Mhz won't be correct for 144Mhz. Are you thinking
a two-band unit or one-band unit?
 

The si5340/si5341 has a 20mhz spi interface,
so frequency updates could be a couple orders of magnitude faster than on the uBitx.
If that's of interest.

The SI5340A-D-GM is $12 for four fully independent low jitter clocks, 0.0001 to 1028 MHz.
A spendy part for an hfsignals product, but really not bad at $3 per oscillator, considering.
Sucks around 1 Watt of 1.8v + 3.3v, probably want to feed it from a couple switchers.

Jerry


On Sat, Apr 28, 2018 at 07:57 am, Jerry Gaffke wrote:
maybe an si5338 or si5341?
 

Farhan while wideband amps exist for 50-500 they are seriously expensive and difficult to build.
It goes whay passt picking a suitable single transistor.? For example an ENI 1-400mhz amp
I've used that does 50W out weighs in at nearly 60 pounds and sucks down nearly 700w!?
Reason class A amps needed to have that much wide band feedback to give 50 db of gain
nearly flat across the range.?

What you would propose is the RF chain of the FT817 (160M though 432) and known
to pop finals despite revisions and protection.? Look at what is done and also the need to?
internally adjust drive for the band in use as the stage gain does vary greatly even for 6
through 432.? Also impedance matching for the range changes greatly so? what they did
was build in a lot of feedback and no small amount of compromise.? That requires more
stages running at low gain to get power and stability.

Oddly enough a single band amp is far cheaper and can be a lot more robust.
I've done single band power chains for 6 through 432 to 100W with far less headaches.
For 6M the IRF510? single ended at 24V does a very respectable 17W or more but the
amp design is distinctly monoband and its performance at 12V, not great.


Allison
 

One huge difference...? The Baofeng cannot do SSB or CW.? There is a whole landmobile industry?
developing what it takes to make a 'feng so cheap. Its heavy but the electrics is remarkable in?
how little is there.

Wide band power amps....? Bench build a few.? Consider stripline and other VHF and UHF?
methods as well as more than two layers.? Impedance control between stages for Decade
ranges is tough at HF for UHF it can hurt.?

SDR generally brings little advantage to VHF and UHF as the power chain is the real effort and
the RX/TX is just a Image reject DCRX with computer overhead.? ?The DVB-T Dongles are
interesting but are lacking the dynamic range.

Allison


Allison
 

Comprehensive info at:

Hopefully helpfully
Dex, ZL2DEX
 

Thanks,
Very useful. Bookmarked.?
- f

On Sat, 28 Apr 2018, 22:46 Dexter N Muir, <dexy@...> wrote:

Comprehensive info at:

Hopefully helpfully
Dex, ZL2DEX
 

MORE...

LO chains for UHF.? Multipliers add noise so if phase noise is a fact at the fundamental output the?
phase noise of a 3x multiple is 10 log(3) worse!? For small values of N that may be fine but
wen N gets to 10 or more its painful.

If you? experience is FM and repeaters none of that applies to SSB weak signal.? I work out to 15 miles
here from? repeaters using a BoFeng on 2 or 70-cm but the repeater has a 6 or 10 db lo angle
antenna on a tall hill.? With the 55W mobile and a simple 1/4 wave whip I've been heard 65 miles
away on the same repeater.

A good 432/435 SSB rig has a NF under a db for the lna and? SSB band widths can hear down
to better than? -147dbm.? Least mine do.? For 2M it only get a little better.? To work out to 100mi
with some degree of repeatability the set up is 160W, RX LNA, and a 11 element 3.7 wavelength
beam up 35ft from what some would call a good location.? UHF with 60W and a 15 element beam
the best shot to date is 68 miles.? ? ?For 6M the game changes as a 5 element beam and 160W
gets me the world at times.? 6M has Eskip aka sporatic E,?ducting, and Aurora, during the open
season I've worked 3000+ miles (Eu countries) using 4W and a square loop. It was much easier
with 100W and a 3 element beam.? The same mobile setup under average conditions 60 miles
to a very good station with beams on a tall hill.? ?For comparison a similar radio to the 6M HB
on 10M during the 2009 solar minimum got me?85 countries for far less effort.? I'm a? hard
core VHF/UHF person.? You have to want to do it.? ?I can say marginal radios especially
receiving do not make the grade.? FT8 mode or JT65 can improve things if all you want
is "contacts" not conversations. But then you need a tx chain that can support full power
out for up to 15 minutes at a time.?

Working the satellites is far different as then you looking 400-6000 miles depending on angle and?
your fighting? path loss and sometimes refraction.? ?SSB through translator sats is interesting but
requires both a good radio with simultaneous RX and TX on different bands so you can hear if
your making it plus total computer control to counteract doppler.? And aim the antenna.? For FM
sats (aka EasySats) two 'fengs a hand mic, a headset, and a simple hand held antenna well do fine

Allison
 

The formulas at the top of that webpage are having trouble representing exponents.
Probably got lost when scraped up with a copy and paste from some other source.

For example:? "Note that many other manufacturers quote?AL?as nH/t2 for both types of material.?"
That should read? ?AL=nH/(t**2)? ?where t**2 is the number of turns squared.
Also:? "Ferrite:? turns = 1000 ((desired L/AL) 0.5) (where L in?mH)?"
should be? ? turns = (1000*(mH/AL))**0.5)? ?=? sqrt(1000*(mH/AL))

But otherwise, a good source of info on torroids.

Here's a very interesting writeup on the sorts stuff that?go wacky when using torroids:
? ??

Jerry, KE7ER



On Sat, Apr 28, 2018 at 10:27 am, Ashhar Farhan wrote:
Thanks,
Very useful. Bookmarked.?
- f
. . .

?

On Sat, 28 Apr 2018, 22:46 Dexter N Muir, <dexy@...> wrote:

Comprehensive info at:

Hopefully helpfully
Dex, ZL2DEX
 

On Fri, Apr 27, 2018 at 10:18 pm, Ashhar Farhan wrote:
Should be mangle an ADE-1 to get at its transformers? Allison, can you help?

Mixers specifically for UHF are easy to do.? 1n5711 is not ideal.? We are now in the
range of bat5x or bat6x SMT series.? Also the mixer does not have to be DBM it can be
rat race or any number of other possible flavors.?

However you need a good solid amount of low noise (under a DB) RF gain before it
and a stable LO or its not going to fun or hear much.? Images hit you? for 3db off the top.
Modding a commercial mixer is way too costly and more effort when a model for the
range is available for the same cost.

Going to a high IF (up to 45mhz or so) means narrow filters at UHF and doing that
without incurring high losses is not simple to build or tune.? ?Gain is cheap if the cost of
MMICs are not off putting but most MMICS are fairly noisy for receiving.? Board materials
like G10 and FR4 are noticeably lossy and the fancy low loss stuff cost dearly.

I'd call 6M the breakpoint for simple design, 2m transitional for understanding VHF
and up design and 432 the starting point for UHF design.? The next bend is around
3000mhz.? I happen to like the world above 3000mhz but I'm likely nuts.

Allison
 

Exactly.
I have one for 6M and another for 4M.
Very small and easily fitted in a case with the ¦Ìbits.
If you want higher power that's another issue.
With just the barefoot transverter and a simple dipole just about 4M high on the roof fed with some 15M RG58 I worked quite a few stations on 4M as can be seen on my 4M loq at QRZ.com?

On Sat, Apr 28, 2018 at 5:06 PM, K9HZ <bill@...> wrote:

If such a radio is just CW and SSB, those ultra-cheap transverters from the Ukraine are by far the best solution.? If the radio will operate FM¡­ that¡¯s where a redesign is required.

?

I¡¯m using one of the transverters now and they work fine with some simple interfacing.

?

?

Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ

?

Owner - Operator

Big Signal Ranch ¨C K9ZC

Staunton, Illinois

?

Owner ¨C Operator

Villa Grand Piton ¨C J68HZ

Soufriere, St. Lucia W.I.

Rent it:

Like us on Facebook!

?

Moderator ¨C North American QRO Group at Groups.IO.

?

email:? bill@...

?

?

From: [email protected] [mailto:[email protected]] On Behalf Of Jerry Gaffke via Groups.Io
Sent: Saturday, April 28, 2018 9:58 AM
To: [email protected]
Subject: Re: [BITX20] mono band 2 meters rig based on the micro BITx circuit #ubitx #2meters

?

Looks like the goal is to build something more challenging than the uBitx.
Beyond that what it is or does is totally up in the air.
Discussion seems to be moving toward a single band rig capable of SSB/CW about uBitx size.

A few thoughts of my own:
Phase noise from that si5351 gets worse as the freq goes up, maybe an si5338 or si5341?
Having all oscillators off a single reference makes calibration much easier.
Could be used for cross band ops if it receives on more bands than it transmits.
A wideband receiver could also be a spectrum analyzer, use digital techniques
on the audio when resolution better than the crystal filters is required.
Transmit mixer, drivers, final could be a separate board for each band desired,
zero transmit boards is an option for receive only.

Jerry


On Sat, Apr 28, 2018 at 05:55 am, Tim Gorman wrote:

I'm lost as to what your goal is here.
1. The baofeng won't do SSB. Are you wanting to build a SSB unit or an
FM unit?
2. Are you thinking of a handheld or a desktop?
3. a phase line at 432Mhz won't be correct for 144Mhz. Are you thinking
a two-band unit or one-band unit?


Virus-free.


 

Yes, Jerry - a case of PEBCAK at the webage's creation. Lack of consultation with a competent Tech, and lack of knowledge of keyboard and capability of software commonly at hand. Any word-processor has Math symbols and can sub/superscript, so sqrt() can be ¡Ì() and **2 can be ^2 or 2 (shifted to LibreOffice Writer then copy-and-paste for them) - much more readable/comprehensible! Might be a good submission to the site?

73
Dex, ZL2DEX
 

I agree with you. I have one on order.

If you already have a good IF system (i.e. the ubitx) why spend money
duplicating it?

tim ab0wr

On Sat, 28 Apr 2018 10:06:06 -0500
"K9HZ" <bill@...> wrote:

If such a radio is just CW and SSB, those ultra-cheap transverters
from the Ukraine are by far the best solution. If the radio will
operate FM¡­ that¡¯s where a redesign is required.



I¡¯m using one of the transverters now and they work fine with some
simple interfacing.





Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ
PJ2/K9HZ



Owner - Operator

Big Signal Ranch ¨C K9ZC

Staunton, Illinois



Owner ¨C Operator

Villa Grand Piton ¨C J68HZ

Soufriere, St. Lucia W.I.

Rent it: www.VillaGrandPiton.com <>

Like us on Facebook! <>



Moderator ¨C North American QRO Group at Groups.IO.



email: <mailto:bill@...> bill@...





From: [email protected] [mailto:[email protected]] On Behalf Of Jerry
Gaffke via Groups.Io Sent: Saturday, April 28, 2018 9:58 AM
To: [email protected]
Subject: Re: [BITX20] mono band 2 meters rig based on the micro BITx
circuit #ubitx #2meters



Looks like the goal is to build something more challenging than the
uBitx. Beyond that what it is or does is totally up in the air.
Discussion seems to be moving toward a single band rig capable of
SSB/CW about uBitx size.

A few thoughts of my own:
Phase noise from that si5351 gets worse as the freq goes up, maybe an
si5338 or si5341? Having all oscillators off a single reference makes
calibration much easier. Could be used for cross band ops if it
receives on more bands than it transmits. A wideband receiver could
also be a spectrum analyzer, use digital techniques on the audio when
resolution better than the crystal filters is required. Transmit
mixer, drivers, final could be a separate board for each band
desired, zero transmit boards is an option for receive only.

Jerry


On Sat, Apr 28, 2018 at 05:55 am, Tim Gorman wrote:

I'm lost as to what your goal is here.
1. The baofeng won't do SSB. Are you wanting to build a SSB unit or an
FM unit?
2. Are you thinking of a handheld or a desktop?
3. a phase line at 432Mhz won't be correct for 144Mhz. Are you
thinking a two-band unit or one-band unit?





---
This email has been checked for viruses by AVG.
KC9SGV
 

¿ªÔÆÌåÓý

Thanks, Mike,
I am looking at all the options.
There are also SDR's that can do the 2.4 GHz uplink.
Couple that to a off the shelf Wifi booster into the RHCP feed for the dish.

Some ideas here...

image1.JPG

image2.JPG

image3.JPG

image4.JPG

image5.JPG

?

Bernie,
KC9SGV


On Apr 28, 2018, at 10:50 AM, Michael Kana <aa9il@...> wrote:

Go with a transverter and use a 10 meter IF.?
I have seen dual band 2 meter/432 MHz transverters out of the Ukraine or options such as Elecraft. Down East Microwave also sold vhf and uhf transverters but I believe they spun that business off to another builder.?
Or find a used one on the auction site.?

I have picked up the complete Elecraft line 6, 2, 222, and 432 used except for the 222 I¡¯m building and driving with my Kx3 or dedicated 10 meter IF radio?
73
Mike AA9IL?

Warning! ?This is transmitted over a non secure medium

On Apr 28, 2018, at 9:57 AM, Jerry Gaffke via Groups.Io <jgaffke@...> wrote:

Looks like the goal is to build something more challenging than the uBitx.
Beyond that what it is or does is totally up in the air.
Discussion seems to be moving toward a single band rig capable of SSB/CW about uBitx size.

A few thoughts of my own:
Phase noise from that si5351 gets worse as the freq goes up, maybe an si5338 or si5341?
Having all oscillators off a single reference makes calibration much easier.
Could be used for cross band ops if it receives on more bands than it transmits.
A wideband receiver could also be a spectrum analyzer, use digital techniques
on the audio when resolution better than the crystal filters is required.
Transmit mixer, drivers, final could be a separate board for each band desired,
zero transmit boards is an option for receive only.

Jerry


On Sat, Apr 28, 2018 at 05:55 am, Tim Gorman wrote:
I'm lost as to what your goal is here.
1. The baofeng won't do SSB. Are you wanting to build a SSB unit or an
FM unit?
2. Are you thinking of a handheld or a desktop?
3. a phase line at 432Mhz won't be correct for 144Mhz. Are you thinking
a two-band unit or one-band unit?

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