¿ªÔÆÌåÓý

Date

Re: VK4PP uBitx LPF BANK add-on Board

Timothy Fidler
 

MRModder it is not so much a a mess. If they realise they cannot safely add an amp and they spin the dice as far as a letter from the FCC/SMA then the sun rises each morning much the same.? The issues for them will be overtaxed components,? vias not fully plated through and needing a soldered in copper stub? and such like.? I guess they did nto figure on getting component removal and SMD soldering skills when they signed up. Bit like the Army or Marines. have to Man up? and tool up? ?:-))? Perhaps? A F could put something like that in his advertising Spiel .. So saith Don Draper... Perhaps not.

Timothy E. Fidler : Engineer BE Mech(1) Auckland , NDT specialist AINDT UT /RT3 , MT2?
Telephone Whangarei?? 022? 691 8405
e: Engstr@...



----- Original Message -----

To:
<[email protected]>
Cc:

Sent:
Sun, 2 Sep 2018 08:07:13 -0500
Subject:
Re: [BITX20] VK4PP uBitx LPF BANK add-on Board


I suppose that does depend on a person¡¯s skill at executing the myriad of expert opinions opined on this group.? I myself do this for a living so I¡¯ve redesigned the entire radio.? That¡¯s one end of the spectrum.? However there is the other end of the spectrum¡­ the guy who may have just received his license and bought a uBITx thinking it was a nice cheap way to enter the world of HF that now has to deal with this (like some friends of mine).? They can either rely on the experts (self-proclaimed or otherwise) to bail them out of this mess or be given a very simple solution that is possible for them to execute. ?¡°Hellish crude¡± in your own words for you¡­ the only option for someone else.

?

?

From: [email protected] [mailto:[email protected]] On Behalf Of Timothy Fidler
Sent: Sunday, September 2, 2018 1:17 AM
To: [email protected]
Subject: Re: [BITX20] VK4PP uBitx LPF BANK add-on Board

?

All understood but it hellish crude for a radio which allegedly has push button RF operation selection.

?

Well it had it ....

?

Just too many design compromises made. If they had gone for 80 40/30 20 and Ten? mtrs? ?with four filters and a diode OR ..(given the limits ofthe Arduino ) all standard stuff ...the whole thing would never have happened.?

?

so it goes.

Timothy E. Fidler : Engineer BE Mech(1) Auckland , NDT specialist AINDT UT /RT3 , MT2?
Telephone Whangarei?? 022? 691 8405
e: Engstr@...

?


----- Original Message -----

?

To:

<[email protected]>

Cc:

?

Sent:

Sun, 2 Sep 2018 01:06:02 -0500

Subject:

Re: [BITX20] VK4PP uBitx LPF BANK add-on Board

I just soldered female BCN connectors to the 4-pin DuPont connectors and plugged the DuPont connectors onto the filter(s)? I then use a double barrel male to connect the filter to the back of the radio.? It¡¯s very simple.? I¡¯m not currently at home or I could post a picture but I think you get the idea.? I suppose you could put this onto a small proto-board easily¡­or even use Kees board if you wanted to do something more official? This approach takes this whole spur removal well within the capabilities of even the person that barely knows which end of the soldering iron to hold.

?

?

From: [email protected] [mailto:[email protected]] On Behalf Of mark bodlovich
Sent: Saturday, September 1, 2018 11:04 PM
To: [email protected]
Subject: Re: [BITX20] VK4PP uBitx LPF BANK add-on Board

?

Mad Radio Modder;
I'm interested in how you put the qrp labs filter board into the ubitx. I built one and have not put it in yet. Looking for good ideas.?
Thanks, Mark N7HWR

?

Virus-free.

?

--

¡­_. _._


Virus-free.

--

¡­_. _._


Re: KD8CEC v.1.095 CW Issue #ubitx #ubitxcw #ubitx-help

 

¿ªÔÆÌåÓý

I have a 3.5 and am patiently waiting on Alan Merrill to update the 3.5 lcd. You can load the released Hmi/tft but will only fill out 3/4 of the larger lcds



On Sep 2, 2018, at 5:00 PM, Art Olson <olson339@...> wrote:

It¡¯s in version 1.097


On Sep 2, 2018, at 4:53 PM, David Posthuma <davep@...> wrote:

KD8CEC ?V.1.095 FEATURE REQUEST ¨C RE: CW Settings. Overall, I love what you have done with version 1.095. However, I wish the CW settings could be managed better. It appears that the only way to change key-type and speed is to push the main encoder, make sure Setup is On, and then find the CW type menu item. In the next firmware revision, can we have the table in the bottom left corner of the display that communicates CW information be selectable and bring us right into a large on-screen menu to make these menu selections one level deep instead of 4-5 levels deep in the menu structure? As it is, CW settings are not intuitive and it¡¯s a bit cumbersome to work with.

?

Please forgive my critique, your work is truly incredible,

?

David A Posthuma, WD8PUO

1 (616) 283-7703

?

From: [email protected] <[email protected]> On Behalf Of David Posthuma
Sent: Sunday, September 02, 2018 4:39 PM
To: [email protected]
Subject: Re: [BITX20] KD8CEC v.1.095 CW Issue #ubitx #ubitxcw #ubitx-help

?

Mike:

?

The 1.095 firmware screen reads ¡°straight¡± for key setting, but when I go into the menu, I cannot find anywhere to change that setting. Nor is the screen label on the screen selectable to change it????? I would think selecting Key-type and keying speed should be a very easy change right from the touchscreen main screen. But I am unable to change any of these settings.

?

David A Posthuma, WD8PUO

1 (616) 283-7703

?

From: [email protected] <[email protected]> On Behalf Of Mike Woods
Sent: Sunday, September 02, 2018 2:45 AM
To: [email protected]
Subject: Re: [BITX20] KD8CEC v.1.095 CW Issue #ubitx #ubitxcw #ubitx-help

?

David

Did you change the setting from ST to IA or IB in the menu?

Mike ZL1AXG

On 1/09/18 2:29 PM, David Posthuma wrote:

I am sure I missed this topic, but my keyer worked fine until I upgraded the firmware to KD8CEC's V. 1.095 for use with my 4.3-inch Nextion?display. Since the upgrade, I can only use a straight?key. What did I miss??

?

--
Mike Woods
mhwoods@...


Re: KD8CEC v.1.095 CW Issue #ubitx #ubitxcw #ubitx-help

 

¿ªÔÆÌåÓý

It has been released. Not sure lcd size you have as he only supports the small size. Lcd.?


On Sep 2, 2018, at 5:00 PM, Art Olson <olson339@...> wrote:

It¡¯s in version 1.097


On Sep 2, 2018, at 4:53 PM, David Posthuma <davep@...> wrote:

KD8CEC ?V.1.095 FEATURE REQUEST ¨C RE: CW Settings. Overall, I love what you have done with version 1.095. However, I wish the CW settings could be managed better. It appears that the only way to change key-type and speed is to push the main encoder, make sure Setup is On, and then find the CW type menu item. In the next firmware revision, can we have the table in the bottom left corner of the display that communicates CW information be selectable and bring us right into a large on-screen menu to make these menu selections one level deep instead of 4-5 levels deep in the menu structure? As it is, CW settings are not intuitive and it¡¯s a bit cumbersome to work with.

?

Please forgive my critique, your work is truly incredible,

?

David A Posthuma, WD8PUO

1 (616) 283-7703

?

From: [email protected] <[email protected]> On Behalf Of David Posthuma
Sent: Sunday, September 02, 2018 4:39 PM
To: [email protected]
Subject: Re: [BITX20] KD8CEC v.1.095 CW Issue #ubitx #ubitxcw #ubitx-help

?

Mike:

?

The 1.095 firmware screen reads ¡°straight¡± for key setting, but when I go into the menu, I cannot find anywhere to change that setting. Nor is the screen label on the screen selectable to change it????? I would think selecting Key-type and keying speed should be a very easy change right from the touchscreen main screen. But I am unable to change any of these settings.

?

David A Posthuma, WD8PUO

1 (616) 283-7703

?

From: [email protected] <[email protected]> On Behalf Of Mike Woods
Sent: Sunday, September 02, 2018 2:45 AM
To: [email protected]
Subject: Re: [BITX20] KD8CEC v.1.095 CW Issue #ubitx #ubitxcw #ubitx-help

?

David

Did you change the setting from ST to IA or IB in the menu?

Mike ZL1AXG

On 1/09/18 2:29 PM, David Posthuma wrote:

I am sure I missed this topic, but my keyer worked fine until I upgraded the firmware to KD8CEC's V. 1.095 for use with my 4.3-inch Nextion?display. Since the upgrade, I can only use a straight?key. What did I miss??

?

--
Mike Woods
mhwoods@...


Re: VK4PP uBitx LPF BANK add-on Board

RICHARD
 

¿ªÔÆÌåÓý

Not surprised at all, the number of hams that ignore the problem and operate any way

Bring back the wofhong

?

Sent from for Windows 10

?


From: [email protected] <[email protected]> on behalf of dfine100@... <dfine100@...>
Sent: Sunday, September 2, 2018 12:38:34 PM
To: [email protected]
Subject: Re: [BITX20] VK4PP uBitx LPF BANK add-on Board
?
I would think that Farhan should put a disclaimer on the hfsigs website stating that the ubitx does not meet some countries (i.e. USA) specifications for legal operation and that it will take a considerable amount of modification to make it meet those specs.? I agree that most new hams buy it thinking all they have to do is connect a few cables and the have a legal ready to go transceiver, when in fact they could buy a used 100 watt transceiver for not much more money that would meet specs.? That's my $.02 opinion.
W0DF


Re: UBITX TX level diagramme

 

MRM,

An example of a DBM radio and oldie is the Atlas180 and friends (210, 215 210x...).
a really simple radio once you cut to the bone.

They use band pass filters for RX and TX pre-power amp and low pass post amp
to take out harmonics.? It was the standard of the day and still is.??

So is the case for bitx20V1, Bitx17, bitx40 and other variations and flavors.
Filter using band pass you get clean, low pass is not adequate filtering save
for harmonics.

Allison


Re: UBITX TX level diagramme

 

On Sun, Sep 2, 2018 at 12:45 PM, Henning Weddig wrote:
The result is intersting: als Allison already stated the gain of the TX stage after the first mixer is 48 dB under these assumptions. My guess is that "normally" a lower level (-10 dBm) will do better in respect of IMD resulting in nearly 60 dB of gain!
Doesn't sound at all correct.? Since the mixer output is in the near -20dbm you need 60db of gain to
achieve +40DBm (10W).? ?I believe I've been saying at least 60db is the target for some time.? What we get is
far less but that an amplifier design issue. FYI most that get maybe 1.7w at 10M are getting far less maybe 48-50db
at 10M.

Most level 7 mixers for "clean" (quoted as they are never pure or clean) output need an input 10db less than
the LO drive minus the insertion loss of the mixer.? So we start at 7dbm (or up to 10 dbM) of LO and that means
input max is -3dbm -another 7db for the mixer loss or minus 10dbm (-10).? Than another 2-4db loss for a
bandpass filter if done right so you at -14.? So you can if lucky get away with 54 db of gain but you need a
tiny bit more for losses and errors.? That is idealized sometimes? you can push the mixer harder, but you
get more unwanted products.

uBitx case is more complicated as you have ground currents inducing signals where they should not be
and a lack of filters to scrub the output.? Now add to that a output low pas filter system that is compromised
by layout.? Now you have a mix of signals that should not be there at all mixing with those that should be
plus excess gain in the IF to overdrive the RF starved ( I measured not more than 3dbm at the mixer) mixer,
output contains a lot of not mathematically predicted outputs because there are inputs not recognized like
a sample of what the power amp is putting out ( coupling though incidental and current loops).

So for a simple 3.5mhz output the mixer may have 45mhx, 48mhz, 3.5mhz, 7mhz, 14mhz, and on
with unpredictable levels and those are the likely inputs the output products are .[...]? many!

Now I did try a 45mhz low pass and it helped a little, less than 6db.? Reason was simple you
have unpredictable paths (ground currents, DC supply lines with RF...) you cannot stop.? But
some are also the nature of the?DBM and cannot be filtered with a low pass filter.? An example
of that is the 2IF (90mhz) mixing with the LO (we will use 28Mhz) of 73mhz to get both 28mhz
output and 90-73 or 17mhz.? A low pass cannot prevent the 17mhz if it is to pass 28mhz.? Also
the existing 33mhz low pass reflects sum products back the mixer so figure all the possible
sums returning to the mixer.

Remember a DBM is both a 4 quadrant multiplier and a chopped sampling system the products
out suggest both as its linear and no linear.? With clean 45mhz you still get diode limited and
squared 45mhz with harmonics circulating internally.

In short you have to map all the possible signals that may exist and their unwanted return
paths and then do the matrix of sums and differences for the fundamentals and their harmonics.

IT made my head hurt and spurtune went nuts listing all of them though the 11th order.

By then levels are no longer an issue.

Allison


Re: Perspex Case

 

Very Nice!

Are the sides open? ?

If they are closed, ?how did you fasten them? ?A photo of the sides would be good.


Irv, W4IWK


Re: KD8CEC v.1.095 CW Issue #ubitx #ubitxcw #ubitx-help

 

¿ªÔÆÌåÓý

Very good. Is version 1.097 stable yet? Are you using it personally?

?

David A Posthuma, WD8PUO

1 (616) 283-7703

?

From: [email protected] <[email protected]> On Behalf Of Art Olson
Sent: Sunday, September 02, 2018 5:01 PM
To: [email protected]
Subject: Re: [BITX20] KD8CEC v.1.095 CW Issue #ubitx #ubitxcw #ubitx-help

?

It¡¯s in version 1.097


On Sep 2, 2018, at 4:53 PM, David Posthuma <davep@...> wrote:

KD8CEC ?V.1.095 FEATURE REQUEST ¨C RE: CW Settings. Overall, I love what you have done with version 1.095. However, I wish the CW settings could be managed better. It appears that the only way to change key-type and speed is to push the main encoder, make sure Setup is On, and then find the CW type menu item. In the next firmware revision, can we have the table in the bottom left corner of the display that communicates CW information be selectable and bring us right into a large on-screen menu to make these menu selections one level deep instead of 4-5 levels deep in the menu structure? As it is, CW settings are not intuitive and it¡¯s a bit cumbersome to work with.

?

Please forgive my critique, your work is truly incredible,

?

David A Posthuma, WD8PUO

1 (616) 283-7703

?

From: [email protected] <[email protected]> On Behalf Of David Posthuma
Sent: Sunday, September 02, 2018 4:39 PM
To: [email protected]
Subject: Re: [BITX20] KD8CEC v.1.095 CW Issue #ubitx #ubitxcw #ubitx-help

?

Mike:

?

The 1.095 firmware screen reads ¡°straight¡± for key setting, but when I go into the menu, I cannot find anywhere to change that setting. Nor is the screen label on the screen selectable to change it????? I would think selecting Key-type and keying speed should be a very easy change right from the touchscreen main screen. But I am unable to change any of these settings.

?

David A Posthuma, WD8PUO

1 (616) 283-7703

?

From: [email protected] <[email protected]> On Behalf Of Mike Woods
Sent: Sunday, September 02, 2018 2:45 AM
To: [email protected]
Subject: Re: [BITX20] KD8CEC v.1.095 CW Issue #ubitx #ubitxcw #ubitx-help

?

David

Did you change the setting from ST to IA or IB in the menu?

Mike ZL1AXG

On 1/09/18 2:29 PM, David Posthuma wrote:

I am sure I missed this topic, but my keyer worked fine until I upgraded the firmware to KD8CEC's V. 1.095 for use with my 4.3-inch Nextion?display. Since the upgrade, I can only use a straight?key. What did I miss??

?

--
Mike Woods
mhwoods@...


Re: KD8CEC v.1.095 CW Issue #ubitx #ubitxcw #ubitx-help

 

¿ªÔÆÌåÓý

It¡¯s in version 1.097


On Sep 2, 2018, at 4:53 PM, David Posthuma <davep@...> wrote:

KD8CEC ?V.1.095 FEATURE REQUEST ¨C RE: CW Settings. Overall, I love what you have done with version 1.095. However, I wish the CW settings could be managed better. It appears that the only way to change key-type and speed is to push the main encoder, make sure Setup is On, and then find the CW type menu item. In the next firmware revision, can we have the table in the bottom left corner of the display that communicates CW information be selectable and bring us right into a large on-screen menu to make these menu selections one level deep instead of 4-5 levels deep in the menu structure? As it is, CW settings are not intuitive and it¡¯s a bit cumbersome to work with.

?

Please forgive my critique, your work is truly incredible,

?

David A Posthuma, WD8PUO

1 (616) 283-7703

?

From: [email protected] <[email protected]> On Behalf Of David Posthuma
Sent: Sunday, September 02, 2018 4:39 PM
To: [email protected]
Subject: Re: [BITX20] KD8CEC v.1.095 CW Issue #ubitx #ubitxcw #ubitx-help

?

Mike:

?

The 1.095 firmware screen reads ¡°straight¡± for key setting, but when I go into the menu, I cannot find anywhere to change that setting. Nor is the screen label on the screen selectable to change it????? I would think selecting Key-type and keying speed should be a very easy change right from the touchscreen main screen. But I am unable to change any of these settings.

?

David A Posthuma, WD8PUO

1 (616) 283-7703

?

From: [email protected] <[email protected]> On Behalf Of Mike Woods
Sent: Sunday, September 02, 2018 2:45 AM
To: [email protected]
Subject: Re: [BITX20] KD8CEC v.1.095 CW Issue #ubitx #ubitxcw #ubitx-help

?

David

Did you change the setting from ST to IA or IB in the menu?

Mike ZL1AXG

On 1/09/18 2:29 PM, David Posthuma wrote:

I am sure I missed this topic, but my keyer worked fine until I upgraded the firmware to KD8CEC's V. 1.095 for use with my 4.3-inch Nextion?display. Since the upgrade, I can only use a straight?key. What did I miss??

?

--
Mike Woods
mhwoods@...


Re: KD8CEC v.1.095 CW Issue #ubitx #ubitxcw #ubitx-help

 

¿ªÔÆÌåÓý

Believe you can push the tune button and dial to setup? ?The deselect until you get to change key. The menu is still there. I am not sure but think you can change it via the screen using 1.097


Art


On Sep 2, 2018, at 4:39 PM, David Posthuma <davep@...> wrote:

Mike:

?

The 1.095 firmware screen reads ¡°straight¡± for key setting, but when I go into the menu, I cannot find anywhere to change that setting. Nor is the screen label on the screen selectable to change it????? I would think selecting Key-type and keying speed should be a very easy change right from the touchscreen main screen. But I am unable to change any of these settings.

?

David A Posthuma, WD8PUO

1 (616) 283-7703

?

From: [email protected] <[email protected]> On Behalf Of Mike Woods
Sent: Sunday, September 02, 2018 2:45 AM
To: [email protected]
Subject: Re: [BITX20] KD8CEC v.1.095 CW Issue #ubitx #ubitxcw #ubitx-help

?

David

Did you change the setting from ST to IA or IB in the menu?

Mike ZL1AXG

On 1/09/18 2:29 PM, David Posthuma wrote:

I am sure I missed this topic, but my keyer worked fine until I upgraded the firmware to KD8CEC's V. 1.095 for use with my 4.3-inch Nextion?display. Since the upgrade, I can only use a straight?key. What did I miss??

?

--
Mike Woods
mhwoods@...


Re: KD8CEC v.1.095 CW Issue #ubitx #ubitxcw #ubitx-help

 

¿ªÔÆÌåÓý

KD8CEC ?V.1.095 FEATURE REQUEST ¨C RE: CW Settings. Overall, I love what you have done with version 1.095. However, I wish the CW settings could be managed better. It appears that the only way to change key-type and speed is to push the main encoder, make sure Setup is On, and then find the CW type menu item. In the next firmware revision, can we have the table in the bottom left corner of the display that communicates CW information be selectable and bring us right into a large on-screen menu to make these menu selections one level deep instead of 4-5 levels deep in the menu structure? As it is, CW settings are not intuitive and it¡¯s a bit cumbersome to work with.

?

Please forgive my critique, your work is truly incredible,

?

David A Posthuma, WD8PUO

1 (616) 283-7703

?

From: [email protected] <[email protected]> On Behalf Of David Posthuma
Sent: Sunday, September 02, 2018 4:39 PM
To: [email protected]
Subject: Re: [BITX20] KD8CEC v.1.095 CW Issue #ubitx #ubitxcw #ubitx-help

?

Mike:

?

The 1.095 firmware screen reads ¡°straight¡± for key setting, but when I go into the menu, I cannot find anywhere to change that setting. Nor is the screen label on the screen selectable to change it????? I would think selecting Key-type and keying speed should be a very easy change right from the touchscreen main screen. But I am unable to change any of these settings.

?

David A Posthuma, WD8PUO

1 (616) 283-7703

?

From: [email protected] <[email protected]> On Behalf Of Mike Woods
Sent: Sunday, September 02, 2018 2:45 AM
To: [email protected]
Subject: Re: [BITX20] KD8CEC v.1.095 CW Issue #ubitx #ubitxcw #ubitx-help

?

David

Did you change the setting from ST to IA or IB in the menu?

Mike ZL1AXG

On 1/09/18 2:29 PM, David Posthuma wrote:

I am sure I missed this topic, but my keyer worked fine until I upgraded the firmware to KD8CEC's V. 1.095 for use with my 4.3-inch Nextion?display. Since the upgrade, I can only use a straight?key. What did I miss??

?

--
Mike Woods
mhwoods@...


Re: KD8CEC v.1.095 CW Issue #ubitx #ubitxcw #ubitx-help

 

¿ªÔÆÌåÓý

Mike:

?

The 1.095 firmware screen reads ¡°straight¡± for key setting, but when I go into the menu, I cannot find anywhere to change that setting. Nor is the screen label on the screen selectable to change it????? I would think selecting Key-type and keying speed should be a very easy change right from the touchscreen main screen. But I am unable to change any of these settings.

?

David A Posthuma, WD8PUO

1 (616) 283-7703

?

From: [email protected] <[email protected]> On Behalf Of Mike Woods
Sent: Sunday, September 02, 2018 2:45 AM
To: [email protected]
Subject: Re: [BITX20] KD8CEC v.1.095 CW Issue #ubitx #ubitxcw #ubitx-help

?

David

Did you change the setting from ST to IA or IB in the menu?

Mike ZL1AXG

On 1/09/18 2:29 PM, David Posthuma wrote:

I am sure I missed this topic, but my keyer worked fine until I upgraded the firmware to KD8CEC's V. 1.095 for use with my 4.3-inch Nextion?display. Since the upgrade, I can only use a straight?key. What did I miss??

?

--
Mike Woods
mhwoods@...


Re: VK4PP uBitx LPF BANK add-on Board

 

¿ªÔÆÌåÓý

Nice and simple.? Why don¡¯t you give us the OSHPark link and we can just order some of these instead of designing our own¡­?

?

?

From: [email protected] [mailto:[email protected]] On Behalf Of James Lynes
Sent: Sunday, September 2, 2018 3:07 PM
To: [email protected]
Subject: Re: [BITX20] VK4PP uBitx LPF BANK add-on Board

?

Received my version of an external LPF board from OSHPark. To second Jerry's comments, OSHPark has a very nice front end process.

?

This board is 1.5in by 3in sized for T68 cores and 1206 caps to provide flexibility for use in future projects. Footprints are provided for both BNC connectors and header pins for input and output.

?

Get a copy of "Make Your Own PCBs with Eagle" by Simon Monk and you can make your own boards for the investment of a small learning curve.

?

James

KEMIQ

?


Virus-free.

--

¡­_. _._


Re: VK4PP uBitx LPF BANK add-on Board

James Lynes
 

Received my version of an external LPF board from OSHPark. To second Jerry's comments, OSHPark has a very nice front end process.

This board is 1.5in by 3in sized for T68 cores and 1206 caps to provide flexibility for use in future projects. Footprints are provided for both BNC connectors and header pins for input and output.

Get a copy of "Make Your Own PCBs with Eagle" by Simon Monk and you can make your own boards for the investment of a small learning curve.

James
KEMIQ


Re: Using radino from ubitx on bitx 40?

 

On Sun, Sep 2, 2018 at 07:11 PM, Tech Guy wrote:
Changing the IF setup in software?
You only need to load the Raduino firmware for BitX40.

original sketch v1.01 with basic LSB functionality:

improved sketch v1.28 with many extra features:


73 Allard PE1NWL


Re: UBITX TX level diagramme

 

Thanks for doing this. The diagram is very informative (need this diagram for the uBITx too). You are correct but a BPF (not LPF) after the mixer is probably better since the mixer is where most of the real nasty harmonics originate...

-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf Of Henning Weddig via Groups.Io
Sent: Sunday, September 2, 2018 2:46 PM
To: [email protected]
Subject: [BITX20] UBITX TX level diagramme

All,

in preparing my talk to be held at the "UKW-Tagung" in Weinheim Germany next Saturday about my UBITX I prepared a level diagramme with some
assumptions: the maximum powe rlevel at the input of a mixer is in the range of -1 dBm (near the 1 dB compression point?)

The result is intersting: als Allison already stated the gain of the TX stage after the first mixer is 48 dB under these assumptions. My guess is that "normally" a lower level (-10 dBm) will do better in respect of IMD resulting in nearly 60 dB of gain!

Another guess for the resultant spurs observed at higher output
frequencies: the bidi amp (45 MHz) is not free of harmonics, i.e. also can and will produce harmonics! If true, these harmonics could be easily removed by introducing a low pass filter between the mixer ("45 MHz
port") and the mixer itself. Who can and will try this mod?

Henning Weddig

DK5LV






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




--
¡­_. _._


Re: Perspex Case

 

¿ªÔÆÌåÓý

Boom Box uBITx¡­

?

?

From: [email protected] [mailto:[email protected]] On Behalf Of george.ellis@...
Sent: Sunday, September 2, 2018 2:28 PM
To: [email protected]
Subject: [BITX20] Perspex Case

?

Just couldn¡¯t hide the beautiful electronics ?


Virus-free.

--

¡­_. _._


UBITX TX level diagramme

 

All,

in preparing my talk to be held at the "UKW-Tagung" in Weinheim Germany next Saturday about my UBITX I prepared a level diagramme with some assumptions: the maximum powe rlevel at the input of a mixer is in the range of -1 dBm (near the 1 dB compression point?)

The result is intersting: als Allison already stated the gain of the TX stage after the first mixer is 48 dB under these assumptions. My guess is that "normally" a lower level (-10 dBm) will do better in respect of IMD resulting in nearly 60 dB of gain!

Another guess for the resultant spurs observed at higher output frequencies: the bidi amp (45 MHz) is not free of harmonics, i.e. also can and will produce harmonics! If true, these harmonics could be easily removed by introducing a low pass filter between the mixer ("45 MHz port") and the mixer itself. Who can and will try this mod?

Henning Weddig

DK5LV


Re: VK4PP uBitx LPF BANK add-on Board

 

I would think that Farhan should put a disclaimer on the hfsigs website stating that the ubitx does not meet some countries (i.e. USA) specifications for legal operation and that it will take a considerable amount of modification to make it meet those specs.? I agree that most new hams buy it thinking all they have to do is connect a few cables and the have a legal ready to go transceiver, when in fact they could buy a used 100 watt transceiver for not much more money that would meet specs.? That's my $.02 opinion.
W0DF


Perspex Case

 

Just couldn¡¯t hide the beautiful electronics ?