Analisis de equipos por W8JI
|Model (in some cases serial included)||MDS||2kHz BDR||10kHz BDR||2kHz IMDR||10kHz IMDR|
|1||R4C heavy mod. Experimental.
See note 5
|2||R4C 17816 med mod.
See note 4
|5||TS-870 Inrad 400Hz IF filter mod (AIP)||-139
|9||FT1000MP 8N370165||-135||73.5||84||62* 75.5**
|11||R4C S/N 22291 stock||-139||80||116||68||86 note3|
|13||FT1000MK V stock||-131||74||86||60 note1A||77 note 1A|
|14||R4C S/N 17816 stock||-132||57||109||48||82 note2|
Note 1: The FT1000MP has the same inherent problem as the FT1000 and FT1000D. A noise-blanker amplifier FET is left on even when the noise blanker is turned off with front panel NB and NB-W switches. This FET connects directly to the IF, and overloads when strong signals are present. Unlike the FT1000 and FT1000D, the front panel noise blanker level control affects the FT1000MP IMD performance. * is with the NB gain control fully advanced, ** is with the NB gain control fully off. In ALL cases the NB off-on switch is OFF!!
Note 1A: Yaesu copied the same basic NB from the FT1000D, and so this radio also has a NB problem even when the NB is switched off. This test was with NB gain menu set for minimum gain. The radio is worse when NB gain is increased in the NB gain menu.
Note 2: This is a MOSFET 2nd mixer R4C, aligned and in good shape but with no changes. This receiver is almost useless for weak signal CW work of any kind because of poor IM performance and filter blow-by.
Note 3: This is a tube 2nd mixer R4C, aligned and in good shape but with no changes. This receiver is almost useless for contesting or crowded bands because of poor IM performance and bad filter blow-by.
Note 4: This is the same receiver in note 2, but with the following changes:
Note 5: Gutted and rebuilt with solid-state double balanced high-level mixers. No vacuum tubes in signal path. Sherwood 600Hz roofing filter. Experimental receiver for full-duplex operation on 160 meters. This receiver allows me to hear weak DX while I am transmitting, as long as they are a few kHz off frequency.