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RE: FT-817 mini review... (with extensive current draw comparisondata)



Hi Marc:

I'm _really_ impressed with this radio, especially on receive (I've used it
loads on RX, but not much for TX). A great RX for satellites. I would even
compare the receiver to an FT-847's for sensitivity and strong signal
handling. No DSP though.

I can assure you that the receiver won't disappoint in strong signal areas.
VHF Pager and UHF Trunk radio here in Central London which kill my 706MkIIG
leave the 817 unphased. IMHO it's worth the battery drain for that RX. See
my little review on http://www.g6lvb.com.

I actually like the menu system because it's works similarly like the
FT-100. I would have liked a slightly larger display though, with another
line telling you which menu you're in. Also putting the volume/sql on the
top left and shifting the antenna and ON button around would have helped my
natural reactions when going for the volume control.

I think this is without a doubt a worthy replacement for the FT-290/690/790.

Tnx for letting me know about the rechargeable mod!

73 Howard G6LVB

-----Original Message-----
From: owner-AMSAT-BB@AMSAT.Org [mailto:owner-AMSAT-BB@AMSAT.Org]On
Behalf Of Marc Holdwick
Sent: 11 January 2001 17:40
To: AMSAT - BB
Subject: [amsat-bb] FT-817 mini review... (with extensive current draw
comparisondata)


I bought a Yaesu FT-817 this last weekend and have begun to play with it.


It is Yaesu's new portable "QRP" rig with 160 meters - 70 cm all mode
capability.

I am using it to replace an FT-690, FT-290, and FT-790 (all MK II versions).

It is quite a neat rig, with quite a few features.  And some you might not
expect in a portable rig.

I won't bore everyone by repeating the feature list - see the Yaesu web page
or data sheet.

The one drawback to the long feature set it that it takes reading the manual
and playing with the rig to learn all of them.  Most of them are handled
through one of two menu systems.

The main problem with the rig is power consumption and power capacity.  It
is powered with either an internal AA pack or an external 8-16 volt supply.

The rig comes with a AA holder for 8 cells.  An optional 1200 mAH ni-cad
pack (not available yet) will also fit inside.  The ni-cad pack can be
charged in the radio via an external 13.8 volt supply.

By a simple mod (see www.mods.dk) one can fool the radio into thinking that
the Yaesu ni-cad pack is installed.  This would allow one to charge user
supplied ni-cads or Ni-MH cells in the radio.

I haven't tested this mod yet.  I will be though.  AA alkalines don't last
very long.  Perhaps only a few hours of operation with very little
transmitting.

The older Yaesu portables draw less current and used C-cells in their
battery pack.  Consequently they lasted much longer on batteries.

I tested the current draw on my FT-290 MKII and the FT-817 and came up with
the following data:


A 13.8 volt supply was used all of the tests.

On TX tests a dummy load and Daiwa CN-465m power/SWR meter was used for very
approximate TX power level measurements.


FT-290 MKII

Receive 1/2 volume noise SSB mode       0.11 A
Receive full volume noise SSB mode        0.12 A
Receive 1/2 volume voice SSB mode        0.14 A
Receive full volume voice SSB mode        0.31 A

Receive 1/2 volume noise FM mode         0.10 A
Receive full volume noise FM mode         0.11 A

Receive squelched                                 0.10 A

TX FM high power (1.8 W meas)              1.18 A
TX FM low power (0.25 W meas)              0.60 A

TX CW high power (1.9 W meas)             1.17 A    (with sidetone)
TX CW low power (0.25 W meas)             0.63 A    (with sidetone)

Backlight draws 90 mA in addition to the above numbers.



FT-817

Receive 1/2 volume noise SSB mode       0.29 A
Receive full volume noise SSB mode        0.31 A
Receive 1/2 volume voice SSB mode        0.33 A
Receive full volume voice SSB mode        0.46 A

Receive 1/2 volume noise FM mode         0.29 A
Receive full volume noise FM mode          0.31 A

Receive squelched                                  0.26 A

TX FM 4/4 power (3.9 W meas)                2.02 A
TX FM 3/4 power (1.9 W meas)                1.48 A
TX FM 2/4 power (0.6 W meas)                1.04 A
TX FM 1/4 power (0.4 W meas)                0.91 A

TX CW 4/4 power (3.9 W meas)               2.07 A    (with sidetone)
TX CW 3/4 power (1.9 W meas)               1.53 A    (with sidetone)
TX CW 2/4 power (0.6 W meas)               1.09 A    (with sidetone)
TX CW 1/4 power (0.4 W meas)               0.97 A    (with sidetone)

Backlight draws 20 mA in addition to the above numbers.



With the above numbers it is quite easy to see why the FT-817 internal
batteries are ill equipped.  The RX current draws are almost 3x that of the
FT-290 while the TX current draws are a bit higher for equivalent output
powers.

To be fair though, the FT-817 is almost 3/4 the size and volume and 1/2
weight of the FT-290.  By adding a small external battery pack, the FT-817
would fare much better on operating time.

I haven't had much opportunity yet to test the actual on-air performance of
the radio.  I am especially curious to check the strong-signal handling
performance (or lack therof) of the radio.  I hope to test that during the
upcoming January VHF contest with a QRP portable operation.

73,

Marc - N8KWX

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