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#ubitx and 6 meters #ubitx


 

Has anyone modified the ubitx to work on 6 meters?? Or would the mods be too extensive for the existing components?
Tom
AB7WT


M Garza
 

I have not tried it, but I am pretty sure receive will work.? Since I only get about one watt on 10 meters, transmitting might not.

Give it a try and let us know.

Marco - KG5PRT?

On Jan 16, 2018 6:10 PM, "Tom Christian" <tmchristian@...> wrote:
Has anyone modified the ubitx to work on 6 meters?? Or would the mods be too extensive for the existing components?
Tom
AB7WT


 

Perhaps with rd16HVF1 and with proper pinout,? one could manage.

Best would be a tap off at befiore PA and manage with MAR preamp and RD16 Final amp.

sarma
?vu3zmv


Regards
MVS Sarma
?

On Wed, Jan 17, 2018 at 8:57 AM, M Garza <mgarza896@...> wrote:
I have not tried it, but I am pretty sure receive will work.? Since I only get about one watt on 10 meters, transmitting might not.

Give it a try and let us know.

Marco - KG5PRT?

On Jan 16, 2018 6:10 PM, "Tom Christian" <tmchristian@...> wrote:
Has anyone modified the ubitx to work on 6 meters?? Or would the mods be too extensive for the existing components?
Tom
AB7WT



 

Thank you, Sarma! (and Marco).? Once my ubitx finally arrives, I'll follow up.
Tom
AB7WT


M Garza
 

If I get some time this evening, I will give it a test.? I will also get to see how the radio handles 30 degree temps (it's in the garage).

Marco - KG5PRT?

On Jan 17, 2018 9:34 AM, "Tom Christian" <tmchristian@...> wrote:
Thank you, Sarma! (and Marco).? Once my ubitx finally arrives, I'll follow up.
Tom
AB7WT


 

Thanks, Marco! I'll be curious to see what you find.
Tom
AB7WT


M Garza
 

Hi Tom,
I didn't get a chance to try it out.? It might not be until the weekend, but I will report back.

Marco - KG5PRT?

On Jan 17, 2018 9:07 PM, "Tom Christian" <tmchristian@...> wrote:
Thanks, Marco! I'll be curious to see what you find.
Tom
AB7WT


M Garza
 

Tom,
I did some tests.? As the board is, it will not transmit much above 30mhz.? There is a 30mhz low pass filter that would have to be bypassed.? I tried 35mhz and I got 1/2 watt.? I get nothing @ 40mhz.

Hope this helps

Marco - KG5PRT?

On Jan 18, 2018 8:31 AM, "M Garza" <mgarza896@...> wrote:
Hi Tom,
I didn't get a chance to try it out.? It might not be until the weekend, but I will report back.

Marco - KG5PRT?

On Jan 17, 2018 9:07 PM, "Tom Christian" <tmchristian@...> wrote:
Thanks, Marco! I'll be curious to see what you find.
Tom
AB7WT


 

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The bigger question is why? ?Is there a constant level of drive from the two stages ahead of the PA? ?If not, there are a lot of changes needed to make it work well above 20 MHz.?


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

?

Owner - Operator

Big Signal Ranch – K9ZC

Staunton, Illinois

?

Owner – Operator

Villa Grand Piton - J68HZ

Soufriere, St. Lucia W.I.

Rent it:


email:??bill@...

?


On Jan 20, 2018, at 10:16 PM, M Garza <mgarza896@...> wrote:

Tom,
I did some tests.? As the board is, it will not transmit much above 30mhz.? There is a 30mhz low pass filter that would have to be bypassed.? I tried 35mhz and I got 1/2 watt.? I get nothing @ 40mhz.

Hope this helps

Marco - KG5PRT?

On Jan 18, 2018 8:31 AM, "M Garza" <mgarza896@...> wrote:
Hi Tom,
I didn't get a chance to try it out.? It might not be until the weekend, but I will report back.

Marco - KG5PRT?

On Jan 17, 2018 9:07 PM, "Tom Christian" <tmchristian@...> wrote:
Thanks, Marco! I'll be curious to see what you find.
Tom
AB7WT


 

Thank you for testing that, Marco!? I really appreciate it!? Thanks also for the comments, Bill.? When my ubitx finally arrives, I'll do some follow up.
Tom
AB7WT


 

50 MHz is a problem simply because the IF is at 45 MHz, very close to 50 MHz. Instead, you can try a converter. An ADE-1 (or a diode mixer made with 1N4148s) fed by a single 2N3904 as an oscillator at 27 or MHz should bring in a lot of local signals. The converter will output at 50-27 = 23 MHz. You can make do with a doubly tuned circuit in the front-end. A pair of bidirectional RF amplfiers, exactly similar to what the ubtix uses will prop up the noise figure and over come the? band pass filter losses.

- f


On Sun, Jan 21, 2018 at 11:51 PM, Tom Christian <tmchristian@...> wrote:
Thank you for testing that, Marco!? I really appreciate it!? Thanks also for the comments, Bill.? When my ubitx finally arrives, I'll do some follow up.
Tom
AB7WT



 

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Yeah yeah everyone and their brother makes a converter from X to 50 MHz but I think the idea is to use something that works without a converter.? Let the experimentation begin!

?

?

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

?

Owner - Operator

Big Signal Ranch – K9ZC

Staunton, Illinois

?

Owner – Operator

Villa Grand Piton – J68HZ

Soufriere, St. Lucia W.I.

Rent it:

Like us on Facebook!

?

?

email:? bill@...

?

From: [email protected] [mailto:[email protected]] On Behalf Of Ashhar Farhan
Sent: Monday, January 22, 2018 1:15 PM
To: [email protected]
Subject: Re: [BITX20] #ubitx and 6 meters

?

50 MHz is a problem simply because the IF is at 45 MHz, very close to 50 MHz. Instead, you can try a converter. An ADE-1 (or a diode mixer made with 1N4148s) fed by a single 2N3904 as an oscillator at 27 or MHz should bring in a lot of local signals. The converter will output at 50-27 = 23 MHz. You can make do with a doubly tuned circuit in the front-end. A pair of bidirectional RF amplfiers, exactly similar to what the ubtix uses will prop up the noise figure and over come the? band pass filter losses.

?

- f

?

?

On Sun, Jan 21, 2018 at 11:51 PM, Tom Christian <tmchristian@...> wrote:

Thank you for testing that, Marco!? I really appreciate it!? Thanks also for the comments, Bill.? When my ubitx finally arrives, I'll do some follow up.
Tom
AB7WT

?


 

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Bill: Why not use a bridge rectifier to keep the correct polarity regardless of input polarity hook up?? I realize this causes a volt drop of up to 1.4 volts. The relay circuit I saw might be better in that regard, however, I? don't? like relays always on.



Sent from my Verizon, Samsung Galaxy smartphone

-------- Original message --------
From: K9HZ <bill@...>
Date: 1/22/18 21:20 (GMT-05:00)
Subject: Re: [BITX20] #ubitx and 6 meters

Yeah yeah everyone and their brother makes a converter from X to 50 MHz but I think the idea is to use something that works without a converter.? Let the experimentation begin!

?

?

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

?

Owner - Operator

Big Signal Ranch – K9ZC

Staunton, Illinois

?

Owner – Operator

Villa Grand Piton – J68HZ

Soufriere, St. Lucia W.I.

Rent it:

Like us on Facebook!

?

?

email:? bill@...

?

From: [email protected] [mailto:[email protected]] On Behalf Of Ashhar Farhan
Sent: Monday, January 22, 2018 1:15 PM
To: [email protected]
Subject: Re: [BITX20] #ubitx and 6 meters

?

50 MHz is a problem simply because the IF is at 45 MHz, very close to 50 MHz. Instead, you can try a converter. An ADE-1 (or a diode mixer made with 1N4148s) fed by a single 2N3904 as an oscillator at 27 or MHz should bring in a lot of local signals. The converter will output at 50-27 = 23 MHz. You can make do with a doubly tuned circuit in the front-end. A pair of bidirectional RF amplfiers, exactly similar to what the ubtix uses will prop up the noise figure and over come the? band pass filter losses.

?

- f

?

?

On Sun, Jan 21, 2018 at 11:51 PM, Tom Christian <tmchristian@...> wrote:

Thank you for testing that, Marco!? I really appreciate it!? Thanks also for the comments, Bill.? When my ubitx finally arrives, I'll do some follow up.
Tom
AB7WT

?


 

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Wrong thread?

?

?

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

?

Owner - Operator

Big Signal Ranch – K9ZC

Staunton, Illinois

?

Owner – Operator

Villa Grand Piton – J68HZ

Soufriere, St. Lucia W.I.

Rent it:

Like us on Facebook!

?

?

email:? bill@...

?

From: [email protected] [mailto:[email protected]] On Behalf Of Leland Lannoye
Sent: Monday, January 22, 2018 10:30 PM
To: [email protected]
Subject: Re: [BITX20] #ubitx and 6 meters

?

Bill: Why not use a bridge rectifier to keep the correct polarity regardless of input polarity hook up?? I realize this causes a volt drop of up to 1.4 volts. The relay circuit I saw might be better in that regard, however, I? don't? like relays always on.

?

?

?

Sent from my Verizon, Samsung Galaxy smartphone

?

-------- Original message --------

From: K9HZ <bill@...>

Date: 1/22/18 21:20 (GMT-05:00)

Subject: Re: [BITX20] #ubitx and 6 meters

?

Yeah yeah everyone and their brother makes a converter from X to 50 MHz but I think the idea is to use something that works without a converter.? Let the experimentation begin!

?

?

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

?

Owner - Operator

Big Signal Ranch – K9ZC

Staunton, Illinois

?

Owner – Operator

Villa Grand Piton – J68HZ

Soufriere, St. Lucia W.I.

Rent it:

Like us on Facebook!

?

?

email:? bill@...

?

From: [email protected] [mailto:[email protected]] On Behalf Of Ashhar Farhan
Sent: Monday, January 22, 2018 1:15 PM
To: [email protected]
Subject: Re: [BITX20] #ubitx and 6 meters

?

50 MHz is a problem simply because the IF is at 45 MHz, very close to 50 MHz. Instead, you can try a converter. An ADE-1 (or a diode mixer made with 1N4148s) fed by a single 2N3904 as an oscillator at 27 or MHz should bring in a lot of local signals. The converter will output at 50-27 = 23 MHz. You can make do with a doubly tuned circuit in the front-end. A pair of bidirectional RF amplfiers, exactly similar to what the ubtix uses will prop up the noise figure and over come the? band pass filter losses.

?

- f

?

?

On Sun, Jan 21, 2018 at 11:51 PM, Tom Christian <tmchristian@...> wrote:

Thank you for testing that, Marco!? I really appreciate it!? Thanks also for the comments, Bill.? When my ubitx finally arrives, I'll do some follow up.
Tom
AB7WT

?


 

Check out the Murata PX1002, a very nice 86.85mhz saw filter from Murata.
Could replace the 45mhz first IF filter.
I bought one to fiddle with, but haven't had time yet.

Jerry, KE7ER


On Mon, Jan 22, 2018 at 06:20 pm, K9HZ wrote:

Yeah yeah everyone and their brother makes a converter from X to 50 MHz but I think the idea is to use something that works without a converter.? Let the experimentation begin!


 

Thanks Ashhar!? I'll follow up while I wait for my ubitx to arrive.? I've been reading like crazy in the meantime.? I just received Wes Hayward's Introduction to RF Design book and have been relearning some basics.....:)
Tom
AB7WT


 

Thanks, Jerry!? Will check out the Murata PX1002.
Tom
AB7WT


 

the murata filter might leak some FM bc qrm. do you have a specsheet for it?
- f

On 23 Jan 2018 9:17 am, "Tom Christian" <tmchristian@...> wrote:
Thanks, Jerry!? Will check out the Murata PX1002.
Tom
AB7WT


 

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Should be below the FM band in most (but not all) countries.

Mike

K5ESS

?

From: [email protected] [mailto:[email protected]] On Behalf Of Ashhar Farhan
Sent: Tuesday, January 23, 2018 8:02 PM
To: [email protected]
Subject: Re: [BITX20] #ubitx and 6 meters

?

the murata filter might leak some FM bc qrm. do you have a specsheet for it?

- f

?

On 23 Jan 2018 9:17 am, "Tom Christian" <tmchristian@...> wrote:

Thanks, Jerry!? Will check out the Murata PX1002.
Tom
AB7WT


 

Datasheet for 86.85mhz SAW filter:??
Here in the US, our FM broadcast band starts at 87.9mhz,
at which point that SAW has 60 or 70dB of attenuation.
However, if you are unlucky, there might be a local channel 6 broadcast TV station
dumping on 82-88mhz,?in which case some shielding would be in order.


On Tue, Jan 23, 2018 at 06:01 pm, Ashhar Farhan wrote:
he murata filter might leak some FM bc qrm. do you have a specsheet for it?
?