[Boatanchors] Subject: SSB Generation - Phasing VS Filter Opinion - HT-32A/B vs HT-37 Example

[Bill Cromwell]

Hi,

First..congratulations on your new HBR. Making anything vs store bought 
automatically is more satisfying. As for your question about phasing vs 
xtal filter you may want to combine both methods in one transmitter.

Your original post asked for input from the hams who have built and used 
both filter and phased SSB generation. I am not quite there but the 
replies have started to 'spread out now. I am mostly a CW op but I did 
briefly use a Heathkit SB-10 (two different periods). I have built xtal 
filters for use on CW. It's so easy even *I* can do it. I have been able 
to buy commercially made SSB xtal filters dirt cheap using the hunt and 
pounce shopping method.

In one of my ARRL publications I saw a comment about using a fixed 
frequency phasing SSB generator along with modest xtal filter to get the 
best results from the "simplest", most economical designs. You might 
want to track that down. I may not remember correctly but It seem that 
was in one of my DeMaw QRP books from ARRL.

I think some unwanted artifacts in the voice quality are introduced by 
the xtal filters due to the steep skirts on the passband. As much as I 
am not a real expert I think the skirts on LC or RC filters are much 
gentler and kinder. I think that is true even if they are adjusted for a 
somewhat narrower pass band.

Good luck with your transmitter project.

73,

Bill  KU8H


-- 
bark less - wag more