One counter intuitive observation I made looking at my FST4W transmission results of early March :

There are quite some occasions when the external spot over hundreds of kilometers have a lower spread than my local KiwiSDR spot is showing (or sometimes the same low spread).
I would expect that the spread would be higher when the distance between Tx and Rx is more.
Just some examples:

time	tx_call	tx_grid	rx_id	receiver	rx_grid	freq	tx_dBm	SNR	drift	mode	S width (mHz)
2023-03-06 13:28:00	F4VTQ	JN28	OE9GHV	KIWI_1	JN47wk	10,140122	30	-10.6	0	3	4
2023-03-06 13:28:00	F4VTQ	JN28	F4VTQ	KIWI_0	JN28ux	10,1401216	30	9.4	0	3	31
2023-03-06 14:14:00	F4VTQ	JN28	OE9GHV	KIWI_3	JN47wk	10,1401214	30	-13.1	0	3	12
2023-03-06 14:14:00	F4VTQ	JN28	OE9GHV	KIWI_1	JN47wk	10,1401214	30	-6	0	3	16
2023-03-06 14:14:00	F4VTQ	JN28	F4VTQ	KIWI_0	JN28ux	10,1402212	30	-11.5	0	3	30
2023-03-06 14:14:00	F4VTQ	JN28	OE9GHV	KIWI_7	JN47wk	10,1401212	30	-7.6	0	3	32
2023-03-06 14:14:00	F4VTQ	JN28	OE9GHV	KIWI_5	JN47wk	10,1401211	30	-8	0	3	33
2023-03-06 16:00:00	F4VTQ	JN28	G3ZIL	G3ZIL_4	IO90hw	10,1401212	30	-12	0	3	5
2023-03-06 16:00:00	F4VTQ	JN28	F4VTQ	KIWI_0	JN28ux	10,1401213	30	0.1	0	3	5
2023-03-06 16:00:00	F4VTQ	JN28	OE9GHV	KIWI_5	JN47wk	10,1401212	30	-10.8	0	3	70
2023-03-06 16:00:00	F4VTQ	JN28	G4ZFQ	G4ZFQ_1	IO90ir	10,140121	30	-14.9	0	3	76
2023-03-06 16:00:00	F4VTQ	JN28	LX1DQ	KIWI_1	JN39cq	10,140123	30	-11	0	3	140
2023-03-06 16:00:00	F4VTQ	JN28	OE9GHV	KIWI_7	JN47wk	10,1401213	30	-10.8	0	3	144
2023-03-06 16:00:00	F4VTQ	JN28	LX1DQ	KIWI_6	JN39cq	10,140123	30	-16	0	3	155
2023-03-06 16:00:00	F4VTQ	JN28	OE9GHV	KIWI_3	JN47wk	10,1401212	30	-16.2	0	3	160
2023-03-06 16:00:00	F4VTQ	JN28	LX1DQ	KIWI_3	JN39cq	10,140122	30	-7	0	3	198
2023-03-06 16:00:00	F4VTQ	JN28	LX1DQ	KIWI_2	JN39cq	10,140116	30	-6	0	3	245
2023-03-06 16:00:00	F4VTQ	JN28	EA8/DF4UE	K_LZ	IL38bp	10,1401211	30	-19.7	0	3	406
2023-03-06 16:00:00	F4VTQ	JN28	OE9GHV	KIWI_1	JN47wk	10,1401211	30	-7.5	0	3	410
2023-03-06 16:00:00	F4VTQ	JN28	EA8/DF4UE	K_40	IL38bp	10,1401214	30	-19.5	0	3	488

Erwin

 I have no immediate answer, but this is an interesting phenomenon. I will add to my list of 'modes I have yet to study' which will be covered in the next paper/presentation.

Please
(a) remind me of the specific transmitter and receiver at your station for these spots and what clocks were used

(b) the time period over which that configuration was stable, i.e. no changes were made, so I can look at statistics over a wider time interval than in your email.


best wishes
Gwyn G3ZIL

Gwyn I will send a .csv file with all the spots in that timeframe with separate sheets per transmitter. These have been explained before : Hermes Lite V2, RFZero, Yaesu FT817nd.
Same effect can be seen with all 3.

Erwin.