[hpsdr] Hermes, Thetis, F3 etc.

[Helmut]

Hi All,

For those, who are interested, some findings concerning Hermes boards with
Thetis:

1. Test boards: Hermes 16 bit and Hermes 14 bit, both produced by Apache
Labs
2. Firmware: 10.4 or rather 10.2
3. Thetis v.2.3.11 (2/14/17), max. sampling rate 1536 ksps for RX1, RX2 
4. Single standard DC supply 13.8 V
5. HP Laptop, Windows 10 Pro, Intel i5, 2 core 2.6 GHz, no router, no switch

I operated both boards at highest sampling rate of 1536 ksps for RX1 and
RX2. Both RX enabled and together with the Third-party-SW Fldigi (VAC and
CAT, PS enabled) to load the interface as much as possible, the boards run
within the test time of 1 hour without any issue.
For measuring purposes I had to remove the PTC fuse F3 in the 5V rail. In
this process I noticed that this component was marked 160/16, with obviously
means Bourns type MF-MSMF 160, 16 Vmax and typically 1.6A hold current /2.8A
trip current. Under the above mentioned conditions I measured a maximal
current of 1.55A.
My personal conclusion:  If the board is equipped with that green colored
fuse 160/16, I see NO need for a hardware modification with the current
features of Thetis. An external 5V supply alters nothing.

73, Helmut, DC6NY