Hello All:

Yeah really! My neighbor set his K40 on fire with about 250 watts, and
wanted another new one as they had a guarantee on them to be replaced. I
went with him to the CB shop down town. The lady threw the K40 antenna
into a large box with even more K40's in it! TILT! And said it will be a
while before I get more in!

I said give the K40 back and we will fix it. The 130 pF capacitor had
fried inside the base of the antenna. It was a common mass produced
cheapie capacitor. I replaced the burnt one with 2 each 260 pF caps
wired in parallel to make the 130 pF value. These where Mica 500 VDC
Capacitors. It was a real Bear it get all put back together. We also
replaced the RG-58C CB cheapie coax with RG142 Teflon coax as this will
handle more power safely than the unknown mass produced cheapie coax.

Besides who wants to pay 25 dollars a pop for a transistor for unknown
coax catching on fire?? I sure don't especially with a 8 pill amp!

The K40 worked great after the mod. A few turns of black tape around the
burnt plastic base assebly and some High Gloss Black Paint make it look
real spif a row, Ten-4! We painted on it K40-1 Can do easy G.I.

Jay in the Mojave


PowerHouse Communications wrote:

So that little capacitor in the base of the coil can handle the full 500
watts?

We're goin' in! good job Jay.

Jay in the Mojave wrote:
We painted on it K40-1 Can do easy G.I.

Jay in the Mojave

On Tue, 24 Oct 2006 17:15:29 -0700, Jay in the Mojave wrote:

Hello All:

Yeah really! My neighbor set his K40 on fire with about 250 watts, and
wanted another new one as they had a guarantee on them to be replaced. I
went with him to the CB shop down town. The lady threw the K40 antenna
into a large box with even more K40's in it! TILT! And said it will be a
while before I get more in!

I said give the K40 back and we will fix it. The 130 pF capacitor had
fried inside the base of the antenna. It was a common mass produced
cheapie capacitor. I replaced the burnt one with 2 each 260 pF caps
wired in parallel to make the 130 pF value.


I thought caps in parallel acted like resisitor in series? That would make it
520 instead of 130. But dman, now you got me thinking. I am going to have to go
look it up. I don't recall for sure.

http://www.play-hookey.com/dc_theory...apacitors.html



These where Mica 500 VDC
Capacitors. It was a real Bear it get all put back together. We also
replaced the RG-58C CB cheapie coax with RG142 Teflon coax as this will
handle more power safely than the unknown mass produced cheapie coax.

Besides who wants to pay 25 dollars a pop for a transistor for unknown
coax catching on fire?? I sure don't especially with a 8 pill amp!

The K40 worked great after the mod. A few turns of black tape around the
burnt plastic base assebly and some High Gloss Black Paint make it look
real spif a row, Ten-4! We painted on it K40-1 Can do easy G.I.

Jay in the Mojave


Where is that cap located? I tossed my K40. One problem was the whipw as too
rigid.

Vinnie S.

I said give the K40 back and we will fix it. The 130 pF capacitor had
fried inside the base of the antenna. It was a common mass produced
cheapie capacitor. I replaced the burnt one with 2 each 260 pF caps
wired in parallel to make the 130 pF value.


I thought caps in parallel acted like resisitor in series? That would make it
520 instead of 130. But dman, now you got me thinking. I am going to have to go
look it up. I don't recall for sure.

http://www.play-hookey.com/dc_theory...apacitors.html

Two caps in parallel are additive.

I may be wrong but I believe the cap value in a K-40 is 55 pf

Vinnie S. wrote:

On Tue, 24 Oct 2006 17:15:29 -0700, Jay in the Mojave wrote:


Hello All:

Yeah really! My neighbor set his K40 on fire with about 250 watts, and
wanted another new one as they had a guarantee on them to be replaced. I
went with him to the CB shop down town. The lady threw the K40 antenna
into a large box with even more K40's in it! TILT! And said it will be a
while before I get more in!

I said give the K40 back and we will fix it. The 130 pF capacitor had
fried inside the base of the antenna. It was a common mass produced
cheapie capacitor. I replaced the burnt one with 2 each 260 pF caps
wired in parallel to make the 130 pF value.



I thought caps in parallel acted like resisitor in series? That would make it
520 instead of 130. But dman, now you got me thinking. I am going to have to go
look it up. I don't recall for sure.

http://www.play-hookey.com/dc_theory...apacitors.html




These where Mica 500 VDC
Capacitors. It was a real Bear it get all put back together. We also
replaced the RG-58C CB cheapie coax with RG142 Teflon coax as this will
handle more power safely than the unknown mass produced cheapie coax.


Besides who wants to pay 25 dollars a pop for a transistor for unknown
coax catching on fire?? I sure don't especially with a 8 pill amp!

The K40 worked great after the mod. A few turns of black tape around the
burnt plastic base assebly and some High Gloss Black Paint make it look
real spif a row, Ten-4! We painted on it K40-1 Can do easy G.I.

Jay in the Mojave



Where is that cap located? I tossed my K40. One problem was the whipw as too
rigid.

Vinnie S.


Hello Vinnie: Yep your right! I stand corrected. Had to wire em in series.

Jay in the Mojave

On Tue, 24 Oct 2006 20:03:17 -0700, Jay in the Mojave wrote:


Where is that cap located? I tossed my K40. One problem was the whipw as too
rigid.

Vinnie S.


Hello Vinnie: Yep your right! I stand corrected. Had to wire em in series.

Jay in the Mojave


The other problem I had with the antenna, was the rigidity, as I mention. The
whip is great on the highway, but go into a bank drive-thru or ot a tree lined
street, and it sound like the roof was going to be torn off.

Vinnie S.

"john" wrote...
the radio I'm looking at uses 8 amps on am and 15 amps on
ssb, on transmit.
I will wire the thing into the circuit when I get it to the motor home
but I would like to use it with a cigarette lighter plug, in the auto en
route.

I would not take the power from the lighter plug.
I don't know how good they make the plugs in America, but I doubt that they are perfect
connections.
Any poor connections where the contacts meet will give a resistance, which will drop voltage
and create heat. The voltage drop will vary with power output, so your supply to the radio
could be bouncing up and down to your voice on SSB... which may cause warbling or other
distortion.
Apart from any radio problems, you have to consider the heat being created in the socket and,
possibly, in the wires to that socket.


Regards,
Peter.
http://www.citizensband.radiouk.com/