Hi All: I'm afraid that I reversed the DC Polarity to my FT-847. Needless to say, "the smoked leaked out", therefore, the 847 has ceased to operate.
I understand that the 847 has protection for careless hams like myself.. I was hopping that someone on the board has had this experience (no need to reveal). Or if someone could let me know what may need to be replaced to get my radio back in working order.
Many Thanks, - Joe Westbrook, K7ZT
IIRC, the 847 has a "protection" diode across the DC input. Connecting the DC backwards will blow the fuse, and probably short the diode. You can download the service manual from the mods.dk website. 73, Jim KQ6EA
--- [email protected] wrote:
Hi All: I'm afraid that I reversed the DC Polarity to my FT-847. Needless to say, "the smoked leaked out", therefore, the 847 has ceased to operate.
I understand that the 847 has protection for careless hams like myself.. I was hopping that someone on the board has had this experience (no need to reveal). Or if someone could let me know what may need to be replaced to get my radio back in working order.
Many Thanks,
- Joe Westbrook, K7ZT
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
On Mon, 24 Dec 2007 15:04:55 -0800 (PST), Jim Jerzycke wrote:
IIRC, the 847 has a "protection" diode across the DC input. Connecting the DC backwards will blow the fuse, and probably short the diode. You can download the service manual from the mods.dk website.
Most well-designed radios have this "suicide diode". It usually shorts, and if it's not big enough and/or the fuse isn't fast enough, it will subsequently burn open and the rest of the radio suffers damage.
The first thing the OP could do is find this diode and remove it from the circuit. If the radio then powers up normally and works, luck was on his side and all that needs to be done is replace the diode. If not, expect blown power deviced in the radio and a trip to the repair shop.
73
-Jim
-- Ham Radio NU0C TR7/RV7, TR6/RV6, T4XC/R4C, L4B, NCL2000, SB104A, R390A, GT550A/RV550A, HyGain 3750, IBM PS/2 - all vintage, all the time!
HyGain 3750 User's Group - http://groups.yahoo.com/group/HyGain_3750/
Don't feel bad,, I had a Kenwood TS-700. every lightning storm I'd unplug it from everything.
It had a built in 110VAC supply. But the 4 connector plug was also the same plug you used for the 12VDC input,, just different pins.
I must have a thousand times pulled this connector before a storm, and re attach it afterwards when I wanted to use the rig,
somehow one day 110VAC went into the 12VDC pins, needless to say the rig did NOT like this even with the rig being off.
LOTS of smoke and missing parts on boards after this happened.
But it was a great rig,
It with NO preamp, but 4 eight elemet yagis i was able with a 40 watt amp I actually worked 22 stations off the moon. and that was LONG before any of this new fangled software recieving stuff, it was strictly with headphones and by ear. way cool,, wouldn't mind having another one.
Joe WB9SBD
Jim Jerzycke wrote:
IIRC, the 847 has a "protection" diode across the DC input. Connecting the DC backwards will blow the fuse, and probably short the diode. You can download the service manual from the mods.dk website. 73, Jim KQ6EA
--- [email protected] wrote:
Hi All: I'm afraid that I reversed the DC Polarity to my FT-847. Needless to say, "the smoked leaked out", therefore, the 847 has ceased to operate.
I understand that the 847 has protection for careless hams like myself.. I was hopping that someone on the board has had this experience (no need to reveal). Or if someone could let me know what may need to be replaced to get my radio back in working order.
Many Thanks,
- Joe Westbrook, K7ZT
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Thanks to the PolySat team at CalPoly, nice scans of the FT-847 manual and schematics are here:
http://polysat.calpoly.edu/earthstation/documents/index.php
Joe wrote:
Don't feel bad,, I had a Kenwood TS-700. every lightning storm I'd unplug it from everything.
It had a built in 110VAC supply. But the 4 connector plug was also the same plug you used for the 12VDC input,, just different pins.
I must have a thousand times pulled this connector before a storm, and re attach it afterwards when I wanted to use the rig,
somehow one day 110VAC went into the 12VDC pins, needless to say the rig did NOT like this even with the rig being off.
LOTS of smoke and missing parts on boards after this happened.
But it was a great rig,
It with NO preamp, but 4 eight elemet yagis i was able with a 40 watt amp I actually worked 22 stations off the moon. and that was LONG before any of this new fangled software recieving stuff, it was strictly with headphones and by ear. way cool,, wouldn't mind having another one.
Joe WB9SBD
Jim Jerzycke wrote:
IIRC, the 847 has a "protection" diode across the DC input. Connecting the DC backwards will blow the fuse, and probably short the diode. You can download the service manual from the mods.dk website. 73, Jim KQ6EA
--- [email protected] wrote:
Hi All: I'm afraid that I reversed the DC Polarity to my FT-847. Needless to say, "the smoked leaked out", therefore, the 847 has ceased to operate.
I understand that the 847 has protection for careless hams like myself.. I was hopping that someone on the board has had this experience (no need to reveal). Or if someone could let me know what may need to be replaced to get my radio back in working order.
Many Thanks,
- Joe Westbrook, K7ZT
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Joe, I've done this - my time, it was my Alinco DR-119 mobile, my only ham radio at the time, reverse polarity, _no fuse_, to a gel cell. I wept.
Anyways, you're probably looking for a smoked diode near the DC input. Can you get ahold of a service manual? Google might assist on that. I'll look this evening to see if I can sort something out.
[email protected] wrote:
Hi All: I'm afraid that I reversed the DC Polarity to my FT-847. Needless to say, "the smoked leaked out", therefore, the 847 has ceased to operate.
I understand that the 847 has protection for careless hams like myself.. I was hopping that someone on the board has had this experience (no need to reveal). Or if someone could let me know what may need to be replaced to get my radio back in working order.
Many Thanks,
- Joe Westbrook, K7ZT
Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
participants (6)
-
Jim Jerzycke -
Jim Shorney -
Joe -
jonny 290 -
k7zt＠suddenlink.net -
Ollie Eisman