[hpsdr] Latency.

[Jeff Cook]

I like controlling my HPSDR transceiver with the HRD program suite, but 
came across a problem with latency which rendered the combination of 
HPSDR and DM780 well nigh unusable.  And by latency I'm talking about a 
gap of up to 5 seconds before HPSDR would respond to a command from HRD, 
which if using digital modes is untenable.  The only reference I found 
to using third-party software was in the SDR1000 operator manual, which 
cites as an example configuring PowerSDR to run with MixW, and advises 
one to configure PowerSDR and MixW's cat for use as with a Kenwood TS 
2000.  This works very well with MixW, and so I did the same with HRD 
which also works but with the latency problem as above.  Now it so 
happens that others on the HRD forum were also talking about latency 
problems in connection with the TS 2000, and so I did nothing assuming 
that HRD's author would put the problem right in the fullness of time. 
(When in doubt blame the author).

A couple of nights back I got to addressing the problem again and 
decided I would try the other cat combinations that are available.  I 
guess what I'm going to say next is as plain as a pike staff to most of 
you, but just in case somebody out there is as daft as me the answer to 
the problem is to configure HRD's connect window as: Company = Flex 
Radio, Radio = PowerSDR and then configured PowerSDR's cat tab as: ID = 
PowerSDR, and I've used a speed of 57,600 for both.  With this 
configuration I have as near as makes no difference zero latency and can 
now enjoy using my favourite transceiver with my favourite digital 
control software. MixW is good but rather dated, whereas the HRD suite 
of programs has a stunning user interface and is undergoing continual 
improvement.

Given the software route involved in my setup i.e., HRD... Virtual Audio 
Cable...Virtual Com Port (out)...Virtual Com Port (in)...Virtual Audio 
Cable...PowerSDR or something like that, I had wondered if latency was 
inevitable, well I guess some is, but now it is just a fraction of a 
second and causes no problem.

Does anybody else have problems in visualising what's going on, or is it 
just me?