In reply to OE4JHW:
I’m trying to decide which ssb filter bandwidth to buy for my FT-897d. I don’t
know whether to get the 2.3 KC, 2.0 KC or 1.8 KC. Does anyone know, for sure, if i will lose any sensitivity if i narrow the selectivity to 1.8 KC? I don’t want to loose my ability to hear weak signals just to help get rid of nearby signals,
I have a hi pass and a low pass filter built into the 897 and an external autek audio filter and adjustable speakers, but they can get noisy when i over use either one of them. I have heard that crystal filters are quieter than what i have now. I also don’t know why some have more poles than others, could someone
tell me about that. thanks for anyone’s consideration and double thanks to anyone who answers my question(s). 73 AK4VU Mike
In reply to MM0FMF:
Read the name of the manufacturer.
Yes, indeed. However, Inrad was the only source I found for the 2.0 filter; hence the personal import.
More in a bit…
In reply to AK4VU
Does anyone know, for sure, if i will lose any sensitivity if i narrow the
selectivity to 1.8 KC?
Not noticed any effect on sensitivity with the 2.0 filter; but it does affect speech quality quite a bit.
73,
Rod
In reply to M0JLA:
Thanks, with that in mind, in might not want the 1.8 Kc. I have set my adjustable filters at 300 hz on the low side and 2.3 Khz on the hi side and the audio was still very good to my ears, but there were times i wished for more side rejection, then when i tightened the bandwidth to 1.8 Khz i get a hollow sound even when nobody is talking and i can’t hear as well (may be my ears). The 2.0 Khz sounds pretty stout so i’ll give it a lot of thought. I can always switch it back off when there isn’t much qrm. Thanks again 73 Mike
In reply to M0JLA:
Thanks, with that in mind, in might not want the 1.8 Kc. I have set my adjustable filters at 300 hz on the low side and 2.3 Khz on the hi side and the audio was still very good to my ears, but there were times i wished for more side rejection, then when i tightened the bandwidth to 1.8 Khz i get a hollow sound even when nobody is talking and i can’t hear as well (may be my ears). The 2.0 Khz sounds pretty stout so i’ll give it a lot of thought. I can always switch it back off when there isn’t much qrm. Thanks again 73 Mike