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Testing VARA.
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Hi All,
We are testing VARA this weekend on 7.101 MHz USB DIAL. Impressive legal mode. Beats P3 on both thruput and robustness. Milspec digital for the ham bands. https://rosmodem.wordpress.com Scroll down Bernie, KC9SGV Chicago
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Dave AA6YQ
-----Original Message-----AA6YQ comments below From: main@digitalradio.groups.io [mailto:main@digitalradio.groups.io] On Behalf Of KC9SGV Sent: Saturday, February 17, 2018 9:26 AM To: main@digitalradio.groups.io Subject: [digitalradio] Testing VARA. We are testing VARA this weekend on 7.101 MHz USB DIAL. Impressive legal mode. Beats P3 on both thruput and robustness. Milspec digital for the ham bands. 73,Does it include a competent busy frequency detector? Dave, AA6YQ
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Andrew OBrien
I will check Dave.
On Tue, Feb 20, 2018 at 10:27 PM, Dave AA6YQ <aa6yq@...> wrote: >>>AA6YQ comments below
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Andrew OBrien
No busy detect feature in the VARA software. Andy K3UK
On Tue, Feb 20, 2018 at 10:29 PM, Andrew OBrien <k3ukandy@...> wrote:
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Station was attended at all times... Has busy frequency detect as incorporated already with BPQ. Will have that also once wrapped inside Winlink Express. Rumors of 30k+ bytes/min on 10 meters in Europe... KC9SGV
On Feb 17, 2018, at 8:25 AM, KC9SGV <kc9sgv@...> wrote:
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Reported in bits per second (as people normally do), that isn’t quite as impressive. About 4000 bps. That is OK, but I implemented a V.29bis modem on a PDP-11 in 1982 and that could do 9600 bps on a clean 4 kHz channel.
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Well, that is impressive too...
VARA is <300 baud, < 2.4 KHz wide. 37,5 bps Symbol Rate with 52 carriers with the full firmware license. KC9SGV
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Andrew O'Brien
Interesting file transfer speeds . I don’t have any experience with Pactor but one of the things I assume about Pactor is that it can do a good job despite weak and noises conditions . Does VARA have the some robust characteristics or does it need bands like 10 to get to higher speeds ?
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Also , I’m puzzled about the Telnet part of all this . I do use RMS express but not sure how you use its Telnet with VARA . Andy K3UK
On Feb 20, 2018, at 11:22 PM, KC9SGV <kc9sgv@...> wrote:
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Andrew OBrien
When using VARA with RMS Express , do you ignore the PTT config in VARA and rely just on the RMS Express settings to PTT the readio ? Andy K3Uk
On Wed, Feb 21, 2018 at 4:58 AM, Andrew O'Brien <andrewobrie@...> wrote:
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Ev Tupis <w2ev@...>
It's easy enough to implement, though. Kudos for thinking about that, Dave! Ev, W2EV
On Tuesday, February 20, 2018, 10:35:18 PM EST, Andrew OBrien <k3ukandy@...> wrote:
No busy detect feature in the VARA software. Andy K3UK
On Tue, Feb 20, 2018 at 10:29 PM, Andrew OBrien <k3ukandy@...> wrote:
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Rick Muething
Walter, Bits per second is related to baud (symbols per second) but one symbol can be 1 or many bits: e.g. One carrier, 50 baud, BPSK = 50 bits/sec One carrier, 50 baud QPSK = 100 bits/sec One carrier 50 baud 16QAM = 200 bits/sec 40 carriers (OFDM) each 50 baud 16QAM = 8000 bits/sec. On HF however with our typical low S:N and multipath it is
usually difficult to exceed 2 bits/sec/Hz. The channel capacity
(theoretical limit on error-free bits/sec) is related to the
channel's S:N as described in Claude Shannon's brilliant paper of
1948. 73, Rick Muething, KN6KB On 2/20/2018 11:24 PM, Walter Underwood wrote:
Reported in bits per second (as people normally do), that isn’t quite as impressive. About 4000 bps. That is OK, but I implemented a V.29bis modem on a PDP-11 in 1982 and that could do 9600 bps on a clean 4 kHz channel.
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Telnet to connect to the VARA modem via RMS Relay. The same as manually setting up a sat phone modem... I use VOX and my Signalink USB. Comparison thruput speeds....not gospel. Bernie, KC9SGV
On Feb 21, 2018, at 3:58 AM, Andrew O'Brien <andrewobrie@...> wrote:
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Bob NW8L
What is the price of the license to unlock the higher capacity modes?
Bob NW8L
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$69 Well worth it. And I have no financial connection with the VARA effort. Just enjoying seeing P3 thruput speeds... KC9SGV
On Feb 21, 2018, at 10:16 AM, Bob NW8L <nw8l@...> wrote:
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I am quite familiar with baud and bits. The V.29 modem I worked on 35 years ago was 9600 bits/sec 16-QAM encoding at 1200 baud. V.29 is still used for faxes.
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And yes, I know about Shannon, too. Getting 4000 bps on 10 meters is great, but I would expect that to be a much better channel than most shortwave paths. It should be lower noise without as much “interesting” ionospheric distortion. Since they were reporting best performance, that could have been line of sight on 10 meters.
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Tony
On 2/20/2018 11:20 PM, KC9SGV wrote:
Any documentation on the web regarding FCC approval? Tony -K2MO
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Tony
Bernie: not able to open the link below. Could you please post the document Or send it direct?
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Thanks, Tony
On Feb 21, 2018, at 12:26 AM, KC9SGV <kc9sgv@...> wrote:
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Andrew O'Brien
Thanks Bernie for sharing this info . I know your call sign from the early days of Winmor and therefor know that you have good experience regarding throughput speeds.
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Andy K3UK.
On Feb 21, 2018, at 12:06 PM, Walter Underwood <wunder@...> wrote:
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Sent and received in Europe over a very difficult HF path with lots of QRM as reported... 
On Feb 21, 2018, at 2:31 PM, Anthony Bombardiere <DXDX@...> wrote:
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