[hpsdr] TAPR Hermes

[Kjell Karlsen]

Hi Bob.

I have tested 3 samples of the original TAPR Hermes and the only problem I  
have seen is a too high voltage drop from U23 to U19, most of it in L22, a  
ferrite bead. This gives a bit too low voltage on the 3.3VA on U13 and  
also 1.2V is a bit low. By just shorting from the output from U23 to the  
input of U16 removes the voltage drop and improves the PHY transfer speed  
at 1GHz.

It should not be necessary to use an external 5V supply. The switch mode  
5V supply runs warm but I have never heard about any problems with it.

F3 has a voltage drop so it can be replaced by a normal 2A fuse OR just  
shorted. I see no need for it as all the series regulators have current  
foldback.

Concerning U23, LT1529 it should not be necessary to do anything to get  
better cooling. I think it is more important to have good air flow around  
the hole Hermes board, may be using a small fan running at low speed. I  
also use to place a copper cooler meant for RAM on top of the ADC and PHY  
chips.

I can not help with the problem with your i7 PC. I think I had something  
similar once with Windows10 Pro and Thetis on an Intel NUC i7 but I do not  
remember what I did to get it working. I may have destroyed the fault, hi!

All the 3 Hermes boards I have tested runs at 384 KHz sampling rate + Wide  
Band.

Good luck!

73, Kjell, LA2NI





På Tue, 07 Jan 2020 14:46:56 +0100, skrev Bob Stricklin  
<bstrick at n5brg.com>:

> ***** High Performance Software Defined Radio Discussion List *****
>
> TAPR Hermes Board Bring-up
>
> I wanted to get my original TAPR Hermes board working with Thetis and  
> Protocol 2. After working on it for a few days I got it working today  
> with Protocol 2 and Thetis  v2.6.8 (11/3/19).
>
> I had to load the firmware in the Hermes board. Had problems doing this;
> 	Tried to load the version 10.3 code first using  
> HPSDRProgrammer_V2_nopcap. Could not communicate with board after this.
> 	Used Bit blaster to load the Bootloader and re-established  
> communications with board.
> 	Then I used HPSDRBootloader to load Firmware 10.3.
>   	All of the above was done with Windows 10 and the Network interface  
> set for manual 10.0.0.1 with no gateway.
>
> 	Loaded Thetis into PC1, Windows 10 Pro with an intel i7 950 @ 3.07 GHz  
> and 24 GB memory.
> 	Using most current Version 1903 at the time.  When I ran Thetis, it  
> gives me the banner page and then the page goes away and Thetis does not  
> execute. Thetis is not listed in active processes.
>
> 	Next I loaded Thetis on PC2, a Slate Windows 10 Pro with an intel  
> i5-6300U CPU @ 2.40GHz with 8 GB of memory.  Using most current Windows  
> distribution Version 1903. Thetis comes up and generates the FFT table  
> and then it runs.
>
> 	I was able to interface with Hermes and turn on the receiver and copy  
> signals. Have not tried to transmit yet but I think that will work.
>
> 	Next I updated the Firmware in Hermes to 10.7 and this is working fine.
>
> 	I have limited the on time not to allow too much heating.
>
> 	Measure current from my 12-volt power source with the following results:
>
> 	Hermes running with J12 set Bootloader mode              300 mA
> 	Hermes running in version 10.3    No Thetis    560 mA    with Thetis  
> 560 mA
> 	Hermes running in version 10.7   No Thetis     770 mA    with Thetis  
> 840 mA
>
>
> My Plans:
>
> 	Install the Hermes board in a larger box and include a fan for cooling.
> 	Install a dedicated power supply – probably 5V only.
> 	May lift the LT1529 Regulator up vertically and add a heatsink with  
> fins if I leave it in play.
> 	Add a relay in the box to do T/R switching.
> 	Add a MIDI connector and get a MIDI interface.
> 	Add a connector to support IF interface to microwave radios.
> 	Find the issue and get PC1 working with Thetis.
> 	Add a dedicated networking card to PC1 and just use it with Hermes.
> 	Add the virtual serial code and get the HRD logging working.
> 	Add needed interface to Stepper antenna controller. Maybe just a CAT  
> interface off
> Hermes.
> 	Add power AMP to box.
>
> Questions:
>
> 	I would welcome comments/warnings about issues I may run into using the  
> older TAPR board.
> 	Any comments about how to debug the problem with Thetis dropping out on  
> PC1? Is there a debug option to turn on and a log file? Have not looked  
> for this yet. I think the source is there so I could start to do my own  
> debug builds but that will be a time sink.
>
> Bob N5BRG
>
> 	
>
> _______________________________________________
> HPSDR Discussion List
> To post msg: hpsdr at openhpsdr.org
> Subscription help:  
> http://lists.openhpsdr.org/listinfo.cgi/hpsdr-openhpsdr.org
> HPSDR web page: http://openhpsdr.org
> Archives: http://lists.openhpsdr.org/pipermail/hpsdr-openhpsdr.org/


-- 
Sendt med Operas e-postklient: http://www.opera.com/mail/