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Author Topic: Idiom SCAF 1 filter  (Read 988 times)

Offline g0iln

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Idiom SCAF 1 filter
« on: January 27, 2014, 15:02:21 UTC »
Hi all,
has anyone used an Idiom SCAF filter on an FT 817? I find the CW portion of 40 Mts total mayhem at the weekends and was wondering if the SCAF  filter would narrow the band enough to make life more pleasant! I have a 50Hz filter fitted in my FT 817 but find the signals so close at times that they "ring"
together.
Any thoughts would be appreciated.
Richard G0ILN.

Offline G0BVZ

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Re: Idiom SCAF 1 filter
« Reply #1 on: January 27, 2014, 16:38:05 UTC »
I find the CW portion of 40 Mts total mayhem at the weekends and was wondering if the SCAF  filter would narrow the band enough to make life more pleasant! I have a 50Hz filter fitted in my FT 817 but find the signals so close at times that they "ring"......


I know exactly what you mean. I'm fairly deaf and want to preserve what's left of my hearing by not listening to loud white noise and pileup mayhem.  I use a 300Hz filter in the rig and a Datong FL3 in the audio line. I think the Datong is the best analogue outboard filter in the world but Datong don't make them any more. They sometimes pop up second hand on Ebay and at rally bring and buys. Prices £40 ~ £90, roughly.  Even they will ring when closed down all the way to 100Hz but they are definitely worth having and they perform well on a number of modes. Demo including the Datong:-

<a href="http://youtu.be/XI2AcJCfOBo" target="_blank" class="aeva_link bbc_link new_win">http://youtu.be/XI2AcJCfOBo</a>


I've been impressed by the performance of outboard DSP speakers on ssb audio signals but they may disappoint on narrow band modes and they ARE pricey.  Before parting with money on these, I'd take a magnifying glass to the specification: if it don't mention CW performance, don't buy!!

I've tried a scaf filter  (Xiegu Technology) and it does a good job on rigs with no/wide internal filters but it doesn't make much of an improvement on a rig with 300Hz filters. Yes, it does make a difference, to a point. Go past that point and you start hearing slightly distracting filtration products.

I avoid pileups like the plague. Life is too short to spend hours trying to crack them. It has been said that the trick with pileups is to either be the first one in or to listen to it while doing a spot of construction: then when there's a lull in the action, pounce! (I put in the last sentence in response to another of your posts elsewhere.  ;D)

Vic /watching the daylight fade.....

Offline IZ5ZCO

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Re: Idiom SCAF 1 filter
« Reply #2 on: January 27, 2014, 17:44:23 UTC »
Hi all, has anyone used an Idiom SCAF filter on an FT 817?


On my FT-817ND I use a 300 Hz Collins CW filter (it works great):

<a href="http://youtu.be/MdlUisMW6iU" target="_blank" class="aeva_link bbc_link new_win">http://youtu.be/MdlUisMW6iU</a>

72 de Nicola

Offline IZ5ZCO

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Re: Idiom SCAF 1 filter
« Reply #3 on: January 27, 2014, 17:53:07 UTC »
SCAF-1 in action:

<a href="http://youtu.be/g8Q-u7-wCL0" target="_blank" class="aeva_link bbc_link new_win">http://youtu.be/g8Q-u7-wCL0</a>
72 de Nicola

Offline G0BVZ

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Re: Idiom SCAF 1 filter
« Reply #4 on: January 27, 2014, 18:14:36 UTC »
That is a great demo, Nicola. Is there one to show how it works when the rig has its own tight filters? My interest is in increasing the 'audio contrast' between the CW tone and background noise. We deaf folk really need to eliminate as much white noise and ringing as possible.