|Above: lifting the lead of one of the Nichicon VX(M) capacitors. I was impressed with the
low ESR readings when testing these older capacitors from a 1970s radio.
I will be stocking up on these types of quality electrolytics for my shop and I plan to sell
them in small quantities to other builders or radio repair people.
|Above: the old fashioned VFO. Simple - NO PLL. These are the kinds of old rigs I like
working on. They are not too cramped and as well..the circuitry is very easy for me to
Also..the parts are not exotic or hard to get replacements for (in general). I have
thousands and thousands of spare parts for older rigs like these.
|Under the VFO circuit board. Note: to the left is the Digital Readout circuitry.
I have quite a few digital parts as well and Im not scared to work on something
as simple as a frequency counter.
|Variable capacitor. This one can tune a whole Megahertz of the
|The coil with the burn marks indicated to me that there must have been some sort of
surge of power problem. There was a problem with the TR switching and I suspected
something was wrong under this circuit board.
---->> So I took lots of pictures -- In case there was a problem when I removed the
board (a good thing to do) and when I took the rotary switch shaft apart and removed
the small circuit board and flipped it up to view the underside.. the (PICTURED RIGHT
--->> BREAK IN THE CIRCUIT FOIL) to the main relay was visible.
|WELL THATS ABOUT IT .. the rig was shipped back to the owner in
NWT (VE8 land). It took me some time..but I did get it going. Alot of
time was spent in the learning curve of learning how the rig worked
and following the schematics. The circuit designations on the
schematic of the Kachina one manual were totally different than the
Kachina 2 version. Made it awkward to follow.
Id like to buy a KACHINA ONE OR KACHINA 2 working or not. -- now
that I know the circuit..I could fix it up for my own use.
73 earl ve3ab
|Link back to PAGE ONE OF THIS KACHINA ARTICLE.
LINK TO MY MAIN HOME PAGE
they are mirror sites. (tnx for looking me up ..earl)
|THESE TWO BAND PASS TRANSFORMERS/FILTERS are the key to the radio
being tuned for either the CB band (below 28 mhz) or the Ham Band (above 28
The rig will operate 26 through 30 mhz but it needs to be optimized to the
section of this spectrum where you expect to do the most operating.
The previous owner had it tuned for the CB band allocation from 26 to 28 mhz. I
am doing this work for the new owner of the rig who is a ham up in VE8 land and
he wants to use it on 10 meter ham band and the 50 mhz band.
The RF output on 11 meters was about 70 watts or so but on 10 meters and 6
meters it was lower than 10 watts.
So..tuning L1 and L2 really got the radio working properly on 28 mhz.
|The Manual. Yes there is a Manual. I have a copy (pdf) on my computer. If you need a copy send me an email.
A copy of snips from the manual below:
|MOVING ON TO THE FINAL PA STAGE.
|The break in the foil is on the circuit board pictured left and to the
left of the relay. In order to gain access to the underside of this
board..you have to remove the shaft connecting collar in the picture
and maneuver the board around in order to gain access to the
underside of the board.
|So ... I now had the Kachina working on receive and it was time to get it to work properly on transmit. Output was strong on the CB part of the bands. You get the 2 CB
allocations by moving the bandswitch down a notch or two from 28 mhz. There are no markings on the front panel but this is how it works.
Anyways..the transmit power was pinning my meter (50 watt slug in Bird 43 wattmeter) but on 10 meters; all I could muster is about 10 watts or maybe a bit less.
|There are three ceramic trimmer capacitors visible on the RF output board. Only one appears on the schematic and that is the HF peaking one at
the output of Q202.
That is on the left hand side of the board. The other two (I think) might be modifications that a previous owner had put into the Kachina. I spoke
to the owner of the Kachina and he has given me the go ahead to remove the two capacitors (modification).
I feel they might be causing some problems on 6 meters. So Im going to remove them and do some testing and I will check the output on the
Spectrum Analyser to see if the output is relatively clean and I will then try to peak the radio up on 6 meters. I assume the previous owner was a
CB operator and did not need to operate on 6.
|Palomar Kachina - A photo essay of my learning the circuitry and
going through the hardware inch by inch and component by
component. by Earl VE3AB
|UPDATED: 4 AUG 2014
(mirror sites) since 2005
|Output coax line (output from the final
output transistors) was lifted and
replaced with RG58 line in order to
directly test the output stage before
low pass filters and the associated
This is a process of "divide and
conquer " trouble shooting.
It eliminates possible trouble areas by
temporarily bypassing them and
You can do this at very low level RF
stages as well.
For the very low level RF transmit
stages..I often use my Oak Hills
Research wattmeter at the 100 mw
setting and I often also use my
spectrum analyser and/or scope.
Another thing you can use to measure
low level RF is a signal probe.
See the HENDRICKS QRP supply web
page and you will see simple test
instruments and instructions on how to