HEROS Tiny-CAT SCR preselector USB to the Native SmartSDR

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Any chance of adding support for the HEROS Tiny-CAT SCR  preselector USB to the Native FLEX-6700, 6500 USB devices like PowerSDR has?
This would allow we, with the older radios the ability to add a preselector for remote use when we are not running a computer and DDUTIL. 
I've been thinking of trying to see if I can convert the HEROS to work with BCD and use a FTDI cable but it would be slick if it had built in USB support on the Radio. 
Thanks
Bret
WX7Y
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WX7Y

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Posted 1 year ago

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Tim - W4TME, Customer Experience Manager

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The 6700 and 6500 already have preselectors.  I doubt integrating this device into SmartSDR would be a feature we would consider adding to the 6300
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WX7Y

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Thanks Tim

Bret
WX7Y
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Jaime Perez

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Well I've got a new 6500 (2 weeks old) replacing my 6300 and I get a very bad Inter-modulation in RX in all the band of 80m from a nearby strong 60Kw BC only when I use the internal preselector from 6500 when the preselector is out "WIDE" it gets normal, I have use in the same position my 6300 without problems so I use an HEROS SCR-Preselector in the Loop A and there is not any Inter-modulation and no Saturation. I have open a ticket but not help at all and no answer.
I don't know if it's a problem of the preselector of this unit or a general problem?
So I have to use the Heros.

Jaime
EA6NB. 
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Tim - W4TME, Customer Experience Manager

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Jamie,

First off, we apologize that you have not received an answer via the HelpDesk to your issue. You should not have to wait as long as you did to get an answer for this particular problem. 

The preselector in FLEX-6500 has an ESD diode before the filter bank.  This is to protect it from static discharges which might damage the LC components.  Under certain circumstances, a very strong nearby signal can cause rectification if the signal level is just below the clamping voltage.  This is what is happening.  As you noted, adding additional filtering to the RX signal path before the preselector using a BCI filter in the RX loop or when the ATU is engaged is attenuating the signal level just below the rectification point. Also when the preselector is not engaged (WIDE mode) the ESD diode for the preselector is not in the RX signal path and there is no more rectification from the strong BC station.

The ESD diode is not malfunctioning.  Your situation is a rare circumstance where the aggregate signal level is just below the clamping threshold point.

Using an external filter device, whether it is a BCI filter (my recommended suggestion) or a preselector, both produce the same effect of reducing the aggregate signal level getting to the preselector ESD diode to a much lower level below the threshold point which is stopping the rectification when the 80m preselector is engaged. 
(Edited)
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Jaime Perez

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Thanks Tim for your help, my QTH has a lot of RFI due at the nearby broadcast stations (3) and particular station so its a rare case, if just I use the internal or external ATU, BCI filter or better Heros in RX Loop will disappear the saturation.
Will be good if Flex adds the Heros Filter to SmartSDR for all we have this preselector.
At the moment if I need it I use it with DDutil where the Heros folows the bands change of the 6500.
73.
Jaime
EA6NB.