[hpsdr] HPSDR Update

[Phil Harman]

Don,

A slight misunderstanding here. What I meant to say was that Mercury 
will operate as a spectrum analyser from 0-55MHz as is - see the Wiki 
under Cyclops for a screen shot of it in action. It's only if you want 
to use it in conjunction with Cyclops (to give 0 - 1000MHz)as a 96MHz 
second IF that you bypass the LPF.

If you want to use it with Cyclops AND a 160-6m receiver then you would 
connect to Mercury past the input LPF when used with Cyclops  and as 
normal via the antenna socket for 160-6m.

We did spend a lot of time and effort trying to switch both the pre-amp 
and LPF out of circuit using either jumpers or a relay.  This 
compromised both the noise floor and introduced some spurs - neither of 
which were acceptable.

Hope that clarifies the situation and you can now enjoy your coffee!

73's Phil....VK6APH






Quoting Don - ki6fom <dbk-forums at cox.net>:

> Is anyone else as upset by this as I am? Mercury is an expensive 
> board and one
> of the things that convinced me to spend the money was that it could 
> also be used
> to provide me with a piece of test equipment that has always been 
> beyond my reach.
> When I saw that if I wanted to have the spectrum analyzer function I 
> have to spend
> another $360 dollars for a second instance of a board I had already 
> ordered (in addition
> to cyclops) I almost choked on my coffee.
>
> Perhaps I was being naive but I'd like to understand why it worked 
> out this way as
> it pretty much puts the spectrum analyzer out of my budget. Phil, can 
> you be a little
> more specific on the trade offs involved?
>
> Thanks
> Don - KI6FOM
>
>
> Phil Harman wrote:
>>
>> 1. I have a prototype of Cyclops working and the performance looks very
>> good. I'm using Mercury at 96MHz as the second IF. To do so I bypass the
>> 55MHz LPF on the front end, this is a permanent by-pass and not somthing
>> that is switchable - believe me we tried hard to make it switchable but this
>> introduced a number of issues that we wern't willing to compromise on.  If
>> you are interested in possibly adding Cyclops to your HPSDR boards in the
>> future then a dedicated Mercury board could be a wise investment.
>>
>
>



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