EMRFD Message Archive 1419
Message Date From Subject 1419 2008-02-06 17:11:41 sp9mrn H-mode mixer questions Hi, I'm thinking 'bout making a H-mode mixer and I've some questions.
1. What is REAL difference in squarer if I use 74HC86 instead of
74AC86 at HF bands, IF 9MHz, max VFO freq. abt 40MHz. Will I see a
difference or not?
2. what is best schematics to use 4:1 transformers from coilcraft. Or
coilcraft is bad idea?
Thanks in advance
1426 2008-02-10 13:49:22 Giancarlo Re: H-mode mixer questions Hi Mac,
please see my comments
1427 2008-02-10 13:58:49 brainerd@wildblue... Re: H-mode mixer questions On 10 Feb 2008 at 21:49, Giancarlo wrote:
> > 1. What is REAL difference in squarer if I use 74HC86 instead ofThere is also the 74AHC86 which is faster and cheaper than the 74AC86.
> > 74AC86 at HF bands, IF 9MHz, max VFO freq. abt 40MHz. Will I see a
> > difference or not?
> The ideal is the 74AC86 as it has very low delay and propagation times
> respect the 74HC86 at least 10x better. This will permit better
> complementary 50-50 switching waveforms
Dave - WB6DHW
1428 2008-02-10 14:28:36 sp9mrn Re: H-mode mixer questions Gian Thank's for comments.
I have been thinking abut HC and coilcraft transformes, because I
have it in my box :-) and it's easy to mahe a quick try.
Of course I know PA site and of course Yours. Inthe fact - Your
article in QST was a motivation to thinh about H-mode.
I also think about frontend - and made a try - making 80m cauer based
on your design -
So thanks also for ideas ;-)
Do You plan to publish something new?