Topband: CY9C

[GEORGE WALLNER]

Jamie,
The amp is water cooled. It is driven to provide 800 W output for the CW 
signal and 200 W for the FT8 signal. The heat spreader temp rarely goes over 
55 C, even in the middle of the day. Water cooling is very effective and of 
course, a must for removing the heat from an enclosed case.

The much (much) bigger challenge for the amp is linearity. The CW and FT8 
signals mix and create an in-band mixing (IMD) product somewhere between 
1,880 and 1,896 kHz, which with poor IP3 could be a couple of Watts. (The 
other mixing products are outside the band and are easily filtered.) The 
signal is CW which is FM modulated by FT8.
Anyway, for anything but a very serous DXpedition, this is way too complex 
and hard to set up. But when you are faced with antenna restrictions and 
limited time to get on the air, it is justified.
73,
George


On Sun, 08 Sep 2024 01:28:43 +0000 WW3S  wrote:
>I'm still trying to wrap my head around the PTT for the amp.....and imagine the duty cycle, that amp must be cooking !!!
>
>73 (thanks for the N5J new one)
>
>Jamie WW3S
>
>
>
>------ Original Message ------
>From "GEORGE WALLNER" <aa7jv at atlanticbb.net>
>To "Rudy Bakalov" <r_bakalov at yahoo.com>
>Cc "Rudy Bakalov via Topband" <topband at contesting.com>
>Date 9/7/2024 9:14:33 PM
>Subject Re: Topband: CY9C
>
>
>>As Jim points out: This is non-trivial.I have not published the details as so far nobody has asked for them.
>>Indeed, it has to be a serious DXpedition to justify the effort needed.
>>George,AA7JV
>>On Sat, 7 Sep 2024 17:07:01 -0400 Rudy Bakalov  wrote:
>>>Is this only for 160? Are the schematics published?
>>>Rudy N2WQ
>>>
>>>Sent using a tiny keyboard.  Please excuse brevity, typos, or inappropriate autocorrect.
>>>
>>>
>>>
>>>>On Sep 7, 2024, at 4:59 PM, GEORGE WALLNER <aa7jv at atlanticbb.net> wrote:
>>>>Rudy,Info at https://www.qrz.com/db/C6AGU73,George
>>>>On Sat, 7 Sep 2024 14:17:45 -0400 Rudy Bakalov via Topband  wrote:
>>>>>How does this work? IF this is indeed the case, this would be agreat solution for multi-op contest stations.
>>>>>
>>>>>Rudy N2WQ
>>>>>
>>>>>Sent using a tiny keyboard.  Please excuse brevity, typos, or inappropriate autocorrect.
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>>On Sep 7, 2024, at 2:01 PM, Jim Brown <jim at audiosystemsgroup.com> wrote: George developed a sophisticated combining network that allowed the two best weak signal modes, CW andFT8, to operate simultaneously into the same TX antenna, and to use the same weak signal RX antennas, allowing them tobe active all night every night! The magnitude of this achievement technically is to realize that the two modes areworking within 20 kHz of each other, and listening within 10 kHz, and the CW station is running high power!
>>>>>>
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