EMRFD Message Archive 7367

Message Date From Subject
7367 2012-03-23 17:27:10 K9SUL HYCAS IF amp for 50KHz IF
Hi,

I am experimenting with the HYCAS IF amp for 50KHz. The first thing I noticed is that the 47uH inductors are too small at 50KHz. What else do I need to adjust? I'd appreciate any suggestions.

73
Kihwal, K9SUL
7368 2012-03-23 19:11:03 kb1gmx Re: HYCAS IF amp for 50KHz IF
7369 2012-03-24 07:25:38 Derward Myrick Re: HYCAS IF amp for 50KHz IF
I do not know how well it would work to add cap to lower the frequency
to 50 KHz but I have some small 262.5 KHz IF cans if you want to try.


Derward Myrick KD5WWI



----- Original Message -----
7370 2012-03-25 07:42:00 Tim Re: HYCAS IF amp for 50KHz IF
What sort of selectivity mechanism would you have for the 50kHz IF? If you've got tuned 50kHz IF transformers then replacing the chokes with transformers to couple to the next stage is 99% of the way there.

If the selectivity is before the 50kHz IF strip and you want a broadband IF stage:

At 50kHz you'd want something like 33mH or larger (millihenry) inductors for the chokes. These could be wound DIY on a bobbin core but more likely you'd just go buy them.

And maybe small pulse transformers with windings in the 10-50 mH range could be usable for broadband transformers at that range. e.g. http://www.murata-ps.com/data/magnetics/kmp_772.pdf

Timing constants for AGC detecti
7371 2012-03-25 22:24:09 Kihwal Lee Re: HYCAS IF amp for 50KHz IF
Thank you all for the suggestions. I have a couple of IF cans of 37mH. I will try these first.

73
Kihwal, K9SUL



7372 2012-03-25 22:24:13 Kihwal Lee Re: HYCAS IF amp for 50KHz IF
Thank you all for the suggestions. I have A couple of IF cans