[ICOM] Fw: Filtering IC 775 DSP

[Anders Janis SM4RNA]

Thanks Dick!

"Older" radios like the 751 can be adjusted as they have separate x-tal 
osc's. A IC-775 only have one osc that suply the whole radio and there by it 
can not be adjusted.

de Anders SM4RNA


----- Original Message ----- 
From: "Edward Dickinson, III" <softblue at alltel.net>
To: "'ICOM Reflector'" <icom at mailman.qth.net>
Sent: Tuesday, June 27, 2006 7:15 PM
Subject: RE: [ICOM] Fw: Filtering IC 775 DSP


> Anders,
>
> Thanks for your interesting comment on unsymetrical filter bandwidth.  I
> have noticed the USB/LSB difference in my stock (filter-wise) IC-751A.  I
> had assumed it to be some internal adjustment.
>
> 73 de Dick - KA5KKT
>
> -----Original Message-----
> From: icom-bounces at mailman.qth.net [mailto:icom-bounces at mailman.qth.net] 
> On
> Behalf Of Anders Janis SM4RNA
> Sent: Tuesday, June 27, 2006 12:20 PM
> To: ICOM Reflector
> Subject: Re: [ICOM] Fw: Filtering IC 775 DSP
>
> The advantage of Inrad is that I have found, is that Inrad filters are
> symetrical. That mean that with Inrad filters re radio sound the same in 
> USB
> and LSB. ICOM filters is often unsymetrical and that can be noted that the
> recived noice sound different in USB and LSB and that mean that the 
> bandwith
> is not the same in LSB and USB. My 1,8kHz ICOM filter is much more narrow 
> on
> USB. You can make the radio to sound the same on USB and LSB by adjusting
> the PBT, but you will get a different setting for each filter.
>
> What bandwith you need greatly depend up on the caracteristic the
> transmitted audio that you receive. Your own prefrenses is also very
> important.
>
> It is up to yourself if the filter is to narrow or not. A friend can not
> tell you what to think.
>
> de Anders SM4RNA
>
>
> ----- Original Message -----
> From: "Anders Janis SM4RNA" <sm4rna at telia.com>
> To: "ICOM Reflector" <icom at mailman.qth.net>
> Sent: Tuesday, June 27, 2006 5:59 PM
> Subject: [ICOM] Fw: Filtering IC 775 DSP
>
>
>> Forwarded upon request:
>>
>>
>>> ----------------
>>> Hello from Poland,
>>>
>>> I have all optional filters installed in my IC 775 DXII, except the
>>> narrow
>>> SSB filter in @455khz slot.
>>>
>>> Some people suggested me to install INRAD 2,1 khz  filter instead of
>>> original FL 222 1,9Khz, saying that the original sounds too narrow and
>>> it's
>>> useless in fact.
>>>
>>> Will be grateful for any advice, maybe someone have already tried both
>>> options...
>>> How about Inrad 1,8 khz filter?
>>>
>>> 73 de Mac SP2XF
>>>
>>
>> ----
>> Your Moderator: Dick Flanagan K7VC, icom-owner at mailman.qth.net
>> Icom Users Net: Sundays, 1700Z, 14.316 MHz
>> Icom FAQ: http://www.qsl.net/icom/
>
> ----
> Your Moderator: Dick Flanagan K7VC, icom-owner at mailman.qth.net
> Icom Users Net: Sundays, 1700Z, 14.316 MHz
> Icom FAQ: http://www.qsl.net/icom/
>
> ----
> Your Moderator: Dick Flanagan K7VC, icom-owner at mailman.qth.net
> Icom Users Net: Sundays, 1700Z, 14.316 MHz
> Icom FAQ: http://www.qsl.net/icom/