Re: Simple spur fix

 

Oos,

You replied to some other issues, so no idea what you replied to.

L5 and & on two board stock values was around 560nH.. they needed two more turns and that did not
help much. These filters are 650 Ohms IMHO.

The sample book had no 720uH so the nearest I took 680nH. Make do!

Still no enlightenment of why SMDs worked.. probably shielding and being close to the ground plane
below.


At 16/10/2018, you wrote:

Are the values of L5 and L7 well calculated? The stock are 720nH, the Raj's are 680nH, but I get on software something like 530nH if the network has a 50 ohm input and a 500 ohm output. Another question is whether or not a different topology of toroids would give better results.

Il 16/ott/2018 05:59, "Raj vu2zap" < rajendrakumargg@...> ha scritto:
A close up sharp photo will help to check.

V3 or V4 ?

Raj

At 16/10/2018, you wrote:
>Hello All,
>
>I just finished implementing the 45 Mhz crystal filter fix with the 7:2 impedance matching transformer on the output of the crystal. Now I am hearing myself in the speaker when I transmit and I am seeing the carrier wave on the SA when I push the PTT on the mic.
>
>I not sure why the crystal filter mod would be related to these two issues. Anyone experience anything similar?
>
>Ripley

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