Dead Yaesu ft-890 Help!
Steve
radio but pushing the power button does nothing.
Used it a few days ago and everything was fine. There was no storm here so
it didn't get zapped.
Is there some kind of fuse inside this radio?
I have limited electronic knowledge, so is there something I can check that
may be a common failure to this rig that I might be able to do?
Bought it on ebay last year and its been flawless, but to me its not worth a
few hundred to ship it out to be fixed.
w9gb
news:b_o3h.7254$3L....@bignews2.bellsouth.net...
"I have limited electronic knowledge -- its not worth a few hundred to ship
it out to be fixed."
Sell it on eBay as a "Broken" or "Tech Special" -- you will get some of your
money back to buy a new radio (with warranty) at your favorite amateur radio
store for Christmas.
gb
sailta...@yahoo.ca
I asuume by "won't power up" you mean completely dead - no lights
meters etc.
The FT-890 uses an external power supply. Are you using the Yaesu
FP-800 Power Supply or another supply? The manual warns users about
reversing the power input leads!!
Try the following:
1. Check the power supply leads to see if you have 13.8 volts. You
will need a digital volt meter but these are pretty cheap at Radio
Shack or your local hardware store. Disconnect the supply from the
receiver and record the voltage.
2. Even if you have 13.8 volts the supply may not be able to provide
enough current if it is defective. Check it with an automobile light
bulb. This will show if there is enough current to power the receiver.
Record the voltage with the light on - still around 13.8V??
3. Reconnect the power supply and measure the voltage as you turn the
power on and off. Any change? If everything is OK so far the power
supply is OK
4. If your meter has an amp scale put the meter to the amps range (2
amps or more). Disconnect the red lead only (leave black attached)
and put the meter in series. (one probe to the red lead and one to the
+ output of power suply). Measure the current with radio power switch
on. Any current flowing?? If you get nothing at all you may have a
loose power connection internally in the radio, a defective power
switch or unfortunately an internal power circuit problem.
Are you confident enough to open the unit and poke around with your
meter??
Good luck - Roger
Steve
or anything comes on.
I have enough nerve to take the covers off and poke around a bit as I have
nothing to lose at this point.
Am retired and divorced once and buying this radio was chore, so if this is
scrapped there will be no replacement.
It has the auto tuner built in, what would be a fair price to ask for it for
parts?
Thanks for help.
<sailta...@yahoo.ca> wrote in message
news:1162791350.9...@k70g2000cwa.googlegroups.com...
Denny
in the club who will be happy to give you a hand trouble shooting your
radio...
As you drive around keep an eye open for the tell tale beam on a tower
where a ham lives... Just ask folks you know or meet if they know any
ham radio operators... Ask the guy next to you at the donut shop...
Walk into the Radio Shack store and ask... If you are in mid Michigan
give me a buzz on here and I will make arrangments for someone to help
you... The CB shop at the local truck stop may be able to offer
advice...
The electronics professor at the local unversity or college... Ask
around the high school and there is likely to be someone who knows
someone... There is help if you just work at finding it... The radio
is unlikely to be scrap...
good luck - denny / k8do
sailta...@yahoo.ca
Denny had some good ideas on how to get your radio fixed by local hams
etc. A radio that is completely dead is easy to troubleshoot -
intermittents are much trickier.
Have you checked the power cable to the radio? Unplug it from the rig
and use the meter and lightbulb to verify that all is OK on the
connecter end that plugs in to the radio. There should be fuses in the
positive and negative leads of the cable. You need to test them with a
meter. Often they look OK to the eye but they are blown. If you don't
have a meter try replacements of the correct amperage rating.
If you decide to take the covers off here are a few tips. Disconnect
the power cable. Get a container to store the screws. They often get
lost and it is impossible to find exact replacements. Do not remove
any boards etc. - this is best left to someone with experience and
proper test equipment. Look in the vicinity of the power socket -
anything burnt or scorched traces on the boards?
I took a preliminary look at the circuit drawings for the FT-890. It
looks like there is a relay that is activated by the power switch.
When the radio was working did you hear a "click" when you turned it
on?? If this relay is blown this is not an expensive repair.
Steve - it can be discouraging when this happens but don't give up on
your radio. Local hams are often willing to help out. There are some
FT-890 owners on the Yahoo group at
http://groups.yahoo.com/group/FT-890
Good luck - Roger
Steve
<sailta...@yahoo.ca> wrote in message
news:1162833515....@k70g2000cwa.googlegroups.com...
>
> I took a preliminary look at the circuit drawings for the FT-890. It
> looks like there is a relay that is activated by the power switch.
> When the radio was working did you hear a "click" when you turned it
> on?? If this relay is blown this is not an expensive repair.
Yes when the radio worked I indeed did hear a click. That's how I knew the
radio wasn't working without even looking at it.
That distinct click wasn't there and I looked at the rig and saw nothing was
on.
I was hoping it was the power supply but I tried to hook the rig to a new
car battery and nothing happened.
The fuses in the line are ok and there is power at the molex connector end
that plugs into the radio.
Thanks for replies and suggestions.
Steve N8NYU
sailta...@yahoo.ca
I only have the downloaded schematics to work with. I was not able to
find a free service manual download on the net so I can only make some
assumptions about circuit operation.
The schematics show the power coming in, via the molex connector, to
the PA board. There is a filter circuit consisting of some capacitors
and a large inductor. The output feeds a relay (clicks at power on)
which provides power to the rig. The relay is controlled by the front
panel switch and a transistor control circuit associated with the PTT.
One thing to try is to check the keyer switch settings on the top of
the radio. The Break In switch may be in the wrong position. Is it in
full or semi?? Try both? Is the keyer in manual?? Remove the
microphone as well in case there is a PTT problem with it.
You could try measuring voltages starting at the molex connector with
the cover off. Put the black probe to ground and trace the circuit
with the red probe. Look for loose connections, burnt traces etc.
There is a set of schematics in pdf form at http://www.kb2ljj.com
Let me know how you make out - Roger
Ralph Mowery
<sailta...@yahoo.ca> wrote in message
news:1162860460....@h54g2000cwb.googlegroups.com...
> Steve,
>
> I only have the downloaded schematics to work with. I was not able to
> find a free service manual download on the net so I can only make some
> assumptions about circuit operation.
>
Did you look at this url for a manual
sailta...@yahoo.ca
They had a lot of manuals but no FT-890 service manuals. However,
they had the user manual and schematic.
Thanks Roger
sailta...@yahoo.ca
I searched through the Yahoo Group - Amateur Repairs for similar "dead"
FT-890 problems. I found one which may be of interest.
As the unit ages oxide builds up on the connector mating surfaces and
sometimes leads to erratic operation. In one case, an FT-890 had
exactly your symptons - dead and the front panel power switch did
nothing. The solution was to disconnect all power and external
connections and remove the covers (saving the screws). Then carefully
disconnect and reconnect, one by one, all the connectors on the
various boards. The disconnect/reconnect scrapes away some of the
oxide on the connectors and restores a low resistance connection. Then
reassemble the unit and try powering up again. Make sure you have
discharged yourself for static (wear cotton clothes and no nylon
carpet!!) prior to starting the job.
If this solves your problem you may be OK for a while. In a few months
it may come back. In that case you should buy some deoxidant from a
radio repair outlet and use it on the contacts for a longer term
solution.
Hope one of these ideas works and it is not a component failure.
Regards - Roger
Steve
This rig might of been mobile as I got a mobile bracket with it and the
power cable was questionable around the fuses (bends in wire) so I replaced
it.
With your suggestions I opened the radio up and started tracing the wires
from behind the molex connector and found where it connected to the circuit
board.
I took the wires loose and cleaned it up cause I kept seeing the voltage on
the multimeter swing. A couple of times I heard the relays partially click
but no power.
Anyways, with the radio in halves I got it to power up, however when I put
it back together it was dead again with no partial relay click.
I took it apart again to the point where it would power up and slowly put
things back and checked power after each segment.
Now the radio is all back tohther and so far still working.
Perhaps something came loose cause I know the pervious owner did a Mars mod
on the radio and who knows what was done if there were other owners.
Thanks for everyones help.
sailta...@yahoo.ca
Thats great news!! Thanks for the reply -it was nice to hear that it
all worked out for you.
Enjoy your rig - Roger
