开云体育

Hi Rahul , Greetings !

?

Wonderful Ideas , Thank you very much indeed !

?

I further explained my project in last post. Kindly ?do look into !

?

73s AP2RF

?

?

From: [email protected] [mailto:[email protected]] On Behalf Of RAHUL SAPRE
Sent: Wednesday, 27 October 2021 1:19 AM
To: [email protected]
Subject: Re: [G6LBQ] Irwell Mixer Stage

?

Hi AP2RF and Andy,

?

-----------------------------------------------------------------------------------------------------------------------------

#1

?

Here is an explanation of how to calculate the values

?

?

Andy is the expert here, (Andy please let us know how to decide on the factor if it should be 5, 10 or something else) but

?

The way to calculate this is as follows you choose a factor (Andy appears to have chosen 5)

?

For the series LC branch, XL should be equal to XC such that it needs to be [50 ohm (design impedance) x the factor]

?

So 50 x 5 = 250 ohm reactive

?

So XL = 2 x pi x f x L

?

XC = 1/ (2 x pi x f x C)

?

Both should equal 250 ohm reactive, see sample calculation of XL below for the series branch.

?

So L = 3584.6 nH? XL = 250 ohm

?? C = 57.4 pf??? XC = 250 ohm

?

?

?

?

For the parallel LC branch, the impedance should be XL = XC = 50/factor = 50/5 = 10 ohm

?

We get

?

C = 1433.8 pf ??XC = 10 ohm

L = 143.4 nH ???XL = 10 ohm

?

Andy has already added a caveat here that availability of components dictated his design choices. (in the pdf)

?

?

?

We get identical results from this online calculator see below ()

?

?

?

?

-----------------------------------------------------------------------------------------------------------------------------

#2

?

With reference to your question for an IF of 9 MHz, see results below for the diplexer values,

?

?

-----------------------------------------------------------------------------------------------------------------------------

#3

?

With reference to your amplifier question, I believe all the transistors you list are obsolete. However I have a stock of 2n5109s and use the amplifier from here, works really well.

?

?

See the mixer section,

?

?

See the broadband amplifier,

?

?

?

See another broadband amplifier using the 2SC5551A (this is also obsolete)

?

?

?

?

?

Vendor for the NE46134 (last 3 remaining)

?

?

?

Another link for the 2N5109

?

?

?

Kind regards