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Any BPF 50 MHz design

"T M"
 

Hello

I search a 50MHz LPF design seem than for U2

Maybe you have this

Thanks by advance

Sincerely
Michel F5OZF
"Paul KE7HR"
 

There is FREE filter design software at:


It also includes a calculator to determine which toroid to use and the number of turns to complete the design.

I usually take what I get from AADE and work with it in the programs from the ARRL book "Expermintal Methods in RF Design" to make it just what I want, but the AADE design usually don't need much attention. I have used it to make filters from LF through low VHF.

Paul KE7HR

--- In QRPLabs@..., "T M" <f5ozf@...> wrote:

Hello

I search a 50MHz LPF design seem than for U2

Maybe you have this

Thanks by advance

Sincerely
Michel F5OZF
"Paul KE7HR"
 

I ran a fast 6 meter filter design from the AADE software and put the schematic and calculated plot in my Photos section KE7HR. This might be a starting point.

Paul KE7HR

--- In QRPLabs@..., "Paul KE7HR" <ke7hr@...> wrote:

There is FREE filter design software at:


It also includes a calculator to determine which toroid to use and the number of turns to complete the design.

I usually take what I get from AADE and work with it in the programs from the ARRL book "Expermintal Methods in RF Design" to make it just what I want, but the AADE design usually don't need much attention. I have used it to make filters from LF through low VHF.

Paul KE7HR

--- In QRPLabs@..., "T M" <f5ozf@> wrote:

Hello

I search a 50MHz LPF design seem than for U2

Maybe you have this

Thanks by advance

Sincerely
Michel F5OZF
Hans Summers
 


All

If someone builds a 6m design, 7-element LPF which will fit on the kit PCB, I am happy to stock them in the shop. I think it would be good if someone proves it works first ;-)

One free Ultimate2 kit (or other kits of equivalent value) to whoever proves the U2 works on 6m, and has reception reports to prove it!

73 Hans G0UPL



On Mon, Jun 17, 2013 at 5:55 PM, Paul KE7HR <ke7hr@...> wrote:
?

I ran a fast 6 meter filter design from the AADE software and put the schematic and calculated plot in my Photos section KE7HR. This might be a starting point.

Paul KE7HR



--- In QRPLabs@..., "Paul KE7HR" wrote:
>
> There is FREE filter design software at:
>
>
> It also includes a calculator to determine which toroid to use and the number of turns to complete the design.
>
> I usually take what I get from AADE and work with it in the programs from the ARRL book "Expermintal Methods in RF Design" to make it just what I want, but the AADE design usually don't need much attention. I have used it to make filters from LF through low VHF.
>
> Paul KE7HR
>
> --- In QRPLabs@..., "T M" wrote:
> >
> > Hello
> >
> > I search a 50MHz LPF design seem than for U2
> >
> > Maybe you have this
> >
> > Thanks by advance
> >
> > Sincerely
> > Michel F5OZF
> >
>
g3zjo
 

¿ªÔÆÌåÓý

On 17/06/2013 23:28, Hans Summers wrote:
If someone builds a 6m design, 7-element LPF which will fit on the kit PCB, I am happy to stock them in the shop.

Done. That was very simple, I designed one some years ago and it is used on my Linear Mixer - Broadband Linear PA - VHF MEPT system, so I knocked up another.

I think it would be good if someone proves it works first ;-)

One free Ultimate2 kit (or other kits of equivalent value) to whoever proves the U2 works on 6m, and has reception reports to prove it!

:-) . What is the penalty for proving that the U2 does not work at 50MHz.?

I should have just measured before building an LPF but then none of us would have been fully happy. The U2 certainly radiates a signal on 50MHz but not via the antenna socket. The square wave drive from the DDS at 28MHz is rather marginal, at 50MHz it is a smear of very low amplitude, the Output FET just gets very hot.
In TX mode the output voltage across 50 Ohms is zero contrasted with the voltage in Standby prior to TX of 0.2V (400uW) at I assume 6.25MHz.

73 Eddie G3ZJO
"Paul KE7HR"
 

The reception reports will have to wait until the updated firmware chip arrives so that I can get a 6 meter signal out of the U2... Else, I have a design that will fit. Also, waiting the filter boards so that I can build the design to fit the U2... They should be in the same shipment.

Good challenge, though!

Paul KE7HR

--- In QRPLabs@..., Hans Summers <hans.summers@...> wrote:

All

If someone builds a 6m design, 7-element LPF which will fit on the kit PCB,
I am happy to stock them in the shop. I think it would be good if someone
proves it works first ;-)

One free Ultimate2 kit (or other kits of equivalent value) to whoever
proves the U2 works on 6m, and has reception reports to prove it!

73 Hans G0UPL
"dl2wb"
 

Any updates on the competition so far ?
Did anyone already claim the U2 ?
The 50 MHz short skip season is not yet over...

Regards from sunny Bavaria,
Tom, DL2WB

--- In QRPLabs@..., "Paul KE7HR" <ke7hr@...> wrote:

The reception reports will have to wait until the updated firmware chip arrives so that I can get a 6 meter signal out of the U2... Else, I have a design that will fit. Also, waiting the filter boards so that I can build the design to fit the U2... They should be in the same shipment.

Good challenge, though!

Paul KE7HR

--- In QRPLabs@..., Hans Summers <hans.summers@> wrote:

All

If someone builds a 6m design, 7-element LPF which will fit on the kit PCB,
I am happy to stock them in the shop. I think it would be good if someone
proves it works first ;-)

One free Ultimate2 kit (or other kits of equivalent value) to whoever
proves the U2 works on 6m, and has reception reports to prove it!

73 Hans G0UPL
Hans Summers
 


Nobody claimed it yet!

73 Hans


On Sat, Jul 27, 2013 at 9:29 PM, dl2wb <t.blinn@...> wrote:
?

Any updates on the competition so far ?
Did anyone already claim the U2 ?
The 50 MHz short skip season is not yet over...

Regards from sunny Bavaria,
Tom, DL2WB



--- In QRPLabs@..., "Paul KE7HR" wrote:
>
> The reception reports will have to wait until the updated firmware chip arrives so that I can get a 6 meter signal out of the U2... Else, I have a design that will fit. Also, waiting the filter boards so that I can build the design to fit the U2... They should be in the same shipment.
>
> Good challenge, though!
>
> Paul KE7HR
>
> --- In QRPLabs@..., Hans Summers wrote:
> >
> > All
> >
> > If someone builds a 6m design, 7-element LPF which will fit on the kit PCB,
> > I am happy to stock them in the shop. I think it would be good if someone
> > proves it works first ;-)
> >
> > One free Ultimate2 kit (or other kits of equivalent value) to whoever
> > proves the U2 works on 6m, and has reception reports to prove it!
> >
> > 73 Hans G0UPL
>

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