I have downloaded both prints and can spend the time to figure out which components need changing to goto the 510 finals but was hoping there was a .txt file on github. I looked and didnt see anything, where do I find those notes?

My sBitx stopped transmitting yesterday and I figured when I troubleshoot this problem, I could go ahead and update the finals at the same time. I have blown two of the IRFZ24N finals so far and now I am ready to move on to a better solution.?

It has been crackling during FT8 recently and the external wattmeter would show spikes in output power, and I figure something in the output chain has failed now that it has went to zero.?

Thanks for?your help in advance,

David

WK4DS?

David, I asked pretty much the same question a?while back, and Evan replied with this document.

I have not started the conversion yet.

On Tue, Mar 26, 2024 at 6:10?AM WK4DS <georgiaphotog@...> wrote:

I have downloaded both prints and can spend the time to figure out which components need changing to goto the 510 finals but was hoping there was a .txt file on github. I looked and didnt see anything, where do I find those notes?

My sBitx stopped transmitting yesterday and I figured when I troubleshoot this problem, I could go ahead and update the finals at the same time. I have blown two of the IRFZ24N finals so far and now I am ready to move on to a better solution.?

It has been crackling during FT8 recently and the external wattmeter would show spikes in output power, and I figure something in the output chain has failed now that it has went to zero.?

Thanks for?your help in advance,

David

WK4DS?

Hi Jens,

Two things come to mind, both around the LPF selection circuits.
1 - There is diode failure such that only one LPF is selected
2 - The HV generating circuit has a failure like Gordon Gibby had.

First, verify the proper operation of the LPF selection changing frequency in receive mode. Then, verify that the correct filter is selected.

If receiving works, verify that the HV voltage is higher than the peak voltage of the output. For 40 watts into 50 ohms, Vpeak = Squartroot(2*50*power) = 63.4 volts.

Be sure to do all tests with a dummy load connected.

73
Evan
AC9TU

... can not open the link.

?

From: Ashhar Farhan

Sent: Saturday, March 30, 2024 6:02 PM

To: [email protected]

Subject: Re: [BITX20] Updating a V2 to V3 finals and need info

?

This?

?

?

On Sat, Mar 30, 2024, 10:22 PM Evan Hand <elhandjr@...> wrote:

Hi Jens,

Two things come to mind, both around the LPF selection circuits.
1 - There is diode failure such that only one LPF is selected
2 - The HV generating circuit has a failure like Gordon Gibby had.

First, verify the proper operation of the LPF selection changing frequency in receive mode. Then, verify that the correct filter is selected.

If receiving works, verify that the HV voltage is higher than the peak voltage of the output. For 40 watts into 50 ohms, Vpeak = Squartroot(2*50*power) = 63.4 volts.

Be sure to do all tests with a dummy load connected.

73
Evan
AC9TU