[ICOM] Icom filters question

[Tony Hwang]

John Geiger wrote:
> Hi Vlad,
>
> That is an interesting observation.  The manual talks about how the
> passband tuning electronically narrows the passband from either side.  Do
> you find that it is enough for SSB?  Also, how does PBT compare to crystal
> filters in terms of skirts and ultimate attenuation?
>
> 73 John AF5CC
>
> On Sat, Jan 30, 2016 at 6:13 PM, V Sidarau <vs.lists at gmail.com> wrote:
>
>> John,
>>
>> I for one don't feel any necessity in a SSB filter because in real life
>> they
>> don't help at all. I used to use them in both IC-756 and IC-775. My
>> personal
>> opinion is, SSB filters are just a waste of money. Roofing filters is what
>> really helps in SSB and nothing else. Just save your money and don't buy
>> the
>> SSB filter. You will not miss anything. Then, the 1.8 KHz 3rd IF filter
>> will
>> not suppress any 2nd IF 250 Hz skirts because the remaining parts of skirts
>> at a reasonable level are much narrower than 1.8 KHz.
>>
>> If you are a serious CW contest operator, you may consider the 250Hz wide
>> 455 Hz filter in addition to the 9 MHz one. Otherwise you may easily drop
>> it, too. A single 250 Hz at 9 MHz is quite enough for daily of semi-serious
>> use.
>>
>> I for one used to use 2 x 250 Hz filters for both CW and RTTY, while the
>> narrow SSB filters were barely used at all. Over 100k QSOs made with such a
>> set-up in CW/SSB/RTTY contesting and DXing.
>>
>> Hope it helps.
>>
>> 73,
>> Vlad VE3IAE
>>
>> --
>>
>>
>>
>>
>> -----Original Message-----
>> From: Icom [mailto:icom-bounces at mailman.qth.net] On Behalf Of John Geiger
>> Sent: Saturday, January 30, 2016 4:59 PM
>> To: ICOM Reflector
>> Subject: [ICOM] Icom filters question
>>
>> I have an Icom 756 original (complete with blue lines in the screen) and
>> want to install both a narrow CW filter and a narrow SSB filter, since I do
>> both modes.  I currently have a FL101 250hz CW filter installed in the 9mhz
>> IF and could get a FL222 1.8KHZ SSB filter for the 455khz IF.  I would use
>> just the FL222 on SSB and use both filters on CW.  So, the 2nd IF would
>> narrow the passband down to 250hz, and the filter in the 3rd IF would maybe
>> narrow it a little more on some blowby or skirts.
>>
>> I am wondering, though, if it would be better to have the wider filter in
>> the 2nd IF and the narrower filter in the 3rd IF?  So I could put a FL223
>> in
>> the 9mhz IF, which on CW would narrow the passband to 1.9khz, and then have
>> the FL53A in the 3rd IF narrowing it down even further.
>>
>> Would this be a better setup, or doesn't it really matter?
>>
>> 73 John AF5CC
>> ----
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>> ----
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>>
> ----
> Your Moderator: Dick Flanagan K7VC: icom-owner at mailman.qth.net
> Icom Users Net: Sundays, 1700Z, 14.316 MHz
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>