I've set my mobile Kenwood D710G on Temp1-1 to "boost" my Kenwood TH-D74 while hiking. Not "fill-in" per se - no need to burden the system. Just to boost the HF signal when at a trailhead with no/little digipeater coverage. Does the below suggest it might have worked?
Bret/N4SRN
N4SRN-7 (Kenwood TH-D74a)
2021-06-12 14:26:54 EDT: N4SRN-7>T3PV0V,N4SRN*,TEMP1*,qAR,N3LLO-2:`cCDl <0x1c>K\>146.520MHz-. ....- ... .-. -.^
2021-06-12 14:30:32 EDT: N4SRN-7>T3PU9Y,N4SRN*,TEMP1*,qAR,N3LLO-2:`cCHl,<0x1d>K\>^
2021-06-12 14:32:34 EDT: N4SRN-7>T3PU9R,N4SRN*,TEMP1*,qAR,N3LLO-2:`cCKl"<0x1d>K\>^
2021-06-12 14:36:38 EDT: N4SRN-7>T3PU7V,N4SRN*,TEMP1*,qAR,N3LLO-2:`cCQl+mK\>^
2021-06-12 14:38:40 EDT: N4SRN-7>T3PU6X,N4SRN*,TEMP1*,qAR,N3LLO-2:`cCPl+>K\>^
2021-06-12 14:42:53 EDT: N4SRN-7>T3PU6R,N4SRN*,TEMP1*,qAR,N3LLO-2:`cC>l6_K\>146.520MHz-. ....- ... .-. -.^
2021-06-12 14:44:54 EDT: N4SRN-7>T3PU6P,TEMP1-1,qAR,N3LLO-2:`cCHl6HK\>^
2021-06-12 14:49:26 EDT: N4SRN-7>T3PU6P,N4SRN*,TEMP1*,qAR,N3LLO-2:`cCWl+>K\>^
2021-06-12 14:50:11 EDT: N4SRN-7>T3PU5X,N4SRN*,TEMP1*,qAR,N3LLO-2:`cCWl6_K\>146.520MHz-. ....- ... .-. -.^
2021-06-12 14:55:18 EDT: N4SRN-7>T3PU5U,N4SRN*,TEMP1*,qAR,N3LLO-2:`cChl-RK\>^
2021-06-12 14:59:22 EDT: N4SRN-7>T3PU5X,N4SRN*,TEMP1*,qAR,N3LLO-2:`cCil#CK\>146.520MHz-. ....- ... .-. -.^
2021-06-12 15:01:46 EDT: N4SRN-7>T3PU6U,N4SRN*,TEMP1*,qAR,N3LLO-2:`cCdl46K\>^
2021-06-12 15:04:00 EDT: N4SRN-7>T3PU7R,N4SRN*,TEMP1*,qAR,N3LLO-2:`cCel-HK\>^
2021-06-12 15:10:12 EDT: N4SRN-7>T3PU9R,N4SRN*,TEMP1*,qAR,N3LLO-2:`cCul-KK\>146.520MHz-. ....- ... .-. -.^
2021-06-12 15:14:26 EDT: N4SRN-7>T3PU9T,N4SRN*,TEMP1*,qAR,N3LLO-2:`cCxl-5K\>^
2021-06-12 15:20:26 EDT: N4SRN-7>T3PV1P,N4SRN*,TEMP1*,qAR,N3LLO-2:`cD%l-'K\>^
2021-06-12 15:22:28 EDT: N4SRN-7>T3PV1U,N4SRN*,TEMP1*,qAR,N3LLO-2:`cD-l,oK\>^
2021-06-12 15:24:30 EDT: N4SRN-7>T3PV1Y,N4SRN*,TEMP1*,qAR,N3LLO-2:`cD6l,sK\>^
2021-06-12 15:26:32 EDT: N4SRN-7>T3PV2P,N4SRN*,TEMP1*,qAR,N3LLO-2:`cD8l K\>146.520MHz-. ....- ... .-. -.^
2021-06-12 15:28:36 EDT: N4SRN-7>T3PV2R,N4SRN*,TEMP1*,qAR,N3LLO-2:`cD?l-<K\>^
2021-06-12 15:30:38 EDT: N4SRN-7>T3PV2T,N4SRN*,TEMP1*,qAR,N3LLO-2:`cDCl,}K\>^
2021-06-12 15:36:48 EDT: N4SRN-7>T3PV3Q,N4SRN*,TEMP1*,qAR,N3LLO-2:`cDal,GK\>^
2021-06-12 15:38:50 EDT: N4SRN-7>T3PV2Y,N4SRN*,TEMP1*,qAR,N3LLO-2:`cDjl">K\>^
2021-06-12 15:49:22 EDT: N4SRN-7>T3PV2U,N4SRN*,TEMP1*,qAR,N3LLO-2:`cDxl*dK\>^
2021-06-12 15:55:40 EDT: N4SRN-7>T3PV3R,N4SRN*,TEMP1*,qAR,N3LLO-2:`cDXl+2K\>^
2021-06-12 15:57:42 EDT: N4SRN-7>T3PV2X,N4SRN*,TEMP1*,qAR,N3LLO-2:`cDNl+&K\>^
2021-06-12 15:59:46 EDT: N4SRN-7>T3PV2U,N4SRN*,TEMP1*,qAR,N3LLO-2:`cDCl+4K\>146.520MHz-. ....- ... .-. -.^
2021-06-12 16:03:50 EDT: N4SRN-7>T3PV1X,N4SRN*,TEMP1*,qAR,N3LLO-2:`cD1l*}K\>^
2021-06-12 16:05:52 EDT: N4SRN-7>T3PV1S,N4SRN*,TEMP1*,qAR,N3LLO-2:`cD'l+2K\>^
2021-06-12 16:10:54 EDT: N4SRN-7>T3PU9V,N4SRN*,TEMP1*,qAR,N3LLO-2:`cCzl5FK\>146.520MHz-. ....- ... .-. -.^
2021-06-12 16:15:06 EDT: N4SRN-7>T3PU8Q,N4SRN*,TEMP1*,qAR,N3LLO-2:`cCll+$K\>^
2021-06-12 16:17:08 EDT: N4SRN-7>T3PU7T,N4SRN*,TEMP1*,qAR,N3LLO-2:`cCfl+MK\>^
2021-06-12 16:19:50 EDT: N4SRN-7>T3PU6S,N4SRN*,TEMP1*,qAR,N3LLO-2:`cCgl,4K\>^
2021-06-12 16:26:54 EDT: N4SRN-7>T3PU5Y,N4SRN*,TEMP1*,qAR,N3LLO-2:`cCNl4jK\>^
2021-06-12 16:29:40 EDT: N4SRN-7>T3PU6R,N4SRN*,TEMP1*,qAR,N3LLO-2:`cC>l6vK\>^
2021-06-12 16:32:28 EDT: N4SRN-7>T3PU6U,N4SRN*,TEMP1*,qAR,N3LLO-2:`cCNl,gK\>^
2021-06-12 16:38:36 EDT: N4SRN-7>T3PU9Q,N4SRN*,TEMP1*,qAR,N3LLO-2:`cCMl*$K\>^
2021-06-12 16:41:46 EDT: N4SRN-7>T3PV0S,N4SRN*,TEMP1*,qAR,N3LLO-2:`cCFl*7K\>^
N4SRN-9 (Kenwood TM-D710G)
2021-06-12 16:45:37 EDT: N4SRN-9>T3PV0U,WIDE1-1,WIDE2-1,qAR,N3LLO-2:`cCCl <0x1c>>/]"3r}=