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I ditto the USB mode. All of my Yaesu rigs (991A, 891, 1200, DX10, etc.) all use just USB. No digital.

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I can send a setup guide if you need one.

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Steven

KC3DSO

kc3dso@...

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?Do they all enable the rear-panel data port in USB mode???? (I know the 891 does, but I am not familiar with the others.)

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Hi Lee,

thanks for your reply. Yes indeed, with the FT DX10 I am using Data-U mode in Winlink-Vara HF. The CAT switches the frequency, to 1.5 kHz below the center frequency. Apparently no issue with other/extra frequency offset in Data-U mode.

On the DX10, when I dial in a frequency in USB mode eg 14300 Mhz, and then switch to Data-U mode, the displayed frequency moves to 14300,7 Mhz.

But on the FT991A, the same happens, regardless of the Other Shift setting (1500 Hz or the default 0 Hz).

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I will try Winlink-Vara HF with the FT991A in USB mode and see how that works connecting to a gateway.

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Note that on some (but not all) Yaesus, you can't access the rear-panel data port in normal USB/LSB modes.? On my FT-857 and FT-891, the 6-pin mini-DIN "data" port is always live.??? On my FT-818, you can receive but not TRANSMIT data in the LSB , USB or FM modes.?? You have to place the radio in "DATA" for any data mode on USB/LSB (i.e. HF) and in "PACKET"? mode for any data mode (not just packet) on FM.

[You DO NOT want to insert complex data modes like VARA into the front-panel MIC jack, where it can? be degraded by uneven frequency response, speech compressors and processors, deviation limiters, etc.? You always want to use the rear-panel "DATA" port if possible.]

Also some (but not all) Yaesus shift the indicated frequency on the display in the DATA mode to reflect the actual center frequency of the transmitted signal, rather than the suppressed carrier frequency as has been universal with hams on USB/LSB voice. ? The "carrier" frequency has NOT changed, just the way it is displayed.?? The amount of this indicated frequency shift is changeable in one of the many menu options in radios have have it. ??

[Note that the? FCC/ITU/military/commercial? convention is to specify the CENTER of an SSB voice channel rather than the suppressed carrier frequency as hams do. I have always thought this was ridiculously ambiguous since the "center" of an SSB channel will depend on the filter passband response of a given radio.]

Confusion reigns because most hams quote the indicated "dial frequency" (suppressed carrier frequency) on USB/LSB when referring to data modes. They fail to realize that the actual RF energy being transmitted is actually hundreds to thousands of Hz higher than the suppressed carrier "dial" frequency, depending on the audio tone frequencies involved.??? VARA is centered on 1500 Hz audio tones. RTTY is customarily centered around 2100 Hz. CW around 700 Hz. Etc.
??? Then various CAT schemes attempt to be more "user-friendly" by calculating and displaying the actual RF transmit frequency, rather than the zero-beat USB carrier frequency.? This will vary by mode.?

Yaesu has been very inconsistent in these distinctions over many models.

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A user recently posted his "BUSY" light being illuminated all the time preventing his transmission.

He showed his waterfall and I asked why he had a notch filter in the middle of his pass band.

When he eliminated the notch filter he was able to transmit because the "BUSY" indication would go out.

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So, my question is: Why would a notch filter inside the pass band cause a "BUSY" indication?

I experimented and found that if I turn on my notch filter outside the 800Hz bandwidth and slowly tuned it toward the VARA 800Hz pass band it would trigger the "BUSY" indicator.

See the attached screenshot of my VARA waterfall.

I slowly tuned the notch from the high-side of the pass band until the "BUSY" lit up.

Mostly curious for my own benefit on signal processing that is going on.

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If this is not the correct forum, please indicate where this question needs to be asked.

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Mark /

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The "BUSY" indicator is similar to the noise-activated squelch on an FM rig.?? It doesn't actually detect specific tones in the passband as an indication of "signal present".? Rather, it looks at the total noise power in the passband.? When the noise power drops due to a signal being present, the channel is considered "BUSY".?? Tuning a notch filter into the passband also decreases the amount of noise in the passband and "fools" the program into thinking the channel is "BUSY".

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I have been monitoring/igating 40-meters APRS-over-VARA for about two weeks now. ??

[The WA8LMF 40-meters APRS-over-VARA igate/mapping webserver is now monitoring 7.083.5 USB full-time 24/7/365 .]

Most of the 40M activity has been long-haul at night from the west coast.? In the daytime, when the useful range on 40 is typically 500 miles (800 km) or so, I have seen few if any stations in the mid-west (my QTH is in central Michigan).? This is now slowly changing....

Today I am copying a short-haul NVIS station on 40 for the first time.??? N5AMD-1 near Battle Creek, MI is only about 50 miles (80 km) from me

This screencap is from my 40M APRS-over-VARA igate, taken just now at 12:36 EST (1736 UTC).? (You are seeing UIview32 running in a virtual machine on a Win7 host running on an Acer E3-111 "netbook" 11.8" mini-laptop.)??

You can see this map display anytime at:

??? ?? Choose the 40 meters APRS-over-VARA link.

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Hello everyone,

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does anyone here use the VARA-HF Decoder () as SWL? What settings do you have to make just for the receiver?

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Thanks and 73

Josef

DE3JGA

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This would not be practical, since nearly all uses of VARA use a two-way hand-shaking ARQ type of operation.????

The only receive-only modes that an SWL could use are APRS, or the monitor mode of VarAC Chat. These are applications that run on top of the VARA modem.? These modes use? one-way beacon-type transmissions that don't expect a reply.

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