A very good friend of mine received a "new"
fundamental crystal for my LPB RC-6A in
the mail. He will be getting it over to
me in the next few days.
The crystal is for 1020 kHz, which is empty
here during the day. The 1020 spot does not have
any local stations around it for several
channels. The rock is an FT-243 (NOS) ordered
from the AF4K website. AF4K sells cool
old radio parts.
The crystal was not very expensive as far
as crystals go. But I am grateful to my
friend because we do not know if it will
work in the RC-6A transmitter. But he said
he would get it for me anyway. He's a real
good guy!
As mentioned before, some manufacturers
might still make crystals that are below 1000 kHz.
And, crystals lower than 1 MHz might have a better chance of operating correctly in the transmitter, which
is now working fine on 860 kHz. Also, we
do not know the transmitter's actual frequency
range, so 1020 may be too high a channel.
The last time I checked for crystals that
could be made to spec for lower than 1 MHz,
I only found one company that would do it.
It was also very expensive - about $75.
And that was many years ago.
So, we will try the 1020 kHz crystal.
Once I have it in hand, I will
have to make an adapter for it to fit into
the RC-6A crystal socket, because it is in
an FT-243 holder. That will be easy, I have
an old empty crystal holder that will fit
in the RC-6A's crystal socket. I can wire
the 1020 FT-243 holder pins into the
bigger empty holder - and then plug it in.
Then there will be the unknowns. Will the crystal
oscillate and be on channel? I won't mind if
it is a little bit off. We'll see.
OK RFB. It's almost time for me to ask you
those specific questions about retuning the
LPB RC-6A. I am almost afraid to do it,
because it is working so well on 860 kHz.
We have several medical situations going on
here. When things slow down, I will start
to try this.
RFB, I might pose my questions soon anyway,
just so I can tuck any info you provide
away in the DOGGRADIO tech notes.
Very Best Wishes,
Bruce, DOGGRADIO STUDIO 2
For some of us, and I am sure this is true for Dog Radio Studio 2, the Part 15 pursuit IS medicinal. It makes us feel better.
If your ailing family members would open their hearts to Part 15 their recovery would be very rapid.
But they are lucky simply to be close to a Part 15 man. The RF energy passes from one to the other.
May your crystal bring you much frequency.
I do appreciate that!
By the way, I sent you an E-mail idea
that may be really stupid, so put
your "anti-stupid goggles" on.
ANTI-STUPID GOGGLES! Available at
Muncho Mart, Best Selling, MOGGS,
Wood Wools, FREEB-X, and other fine stores.
This week only 1/2 price with coupon.
Except in Alaska and Nebraska. Tell
them Road Hog Moran sent you and get a
free Fruit Phone! Only Peach and Grape
available, as long as supplies last.
Bruce, DRS2
Bruce, I didn't need the "stupid goggles" for your e-mail.
It made perfect sense and speaks to thoughts I have as well.
To be polite to general readers, it was advice about "content" on the possibly wide-ranging neutral injection carrier current radio station now under development. I agree with the advice.
As a wise philosopher once said, "It must be suitable for public consumption."
Oh, but that's a difficult quest. I think someone also said, "You must know your audience." Well how....????
"As a wise philosopher once said, "It must be suitable for public consumption."
There is a flaw in that philosopher's statement. The public consists of a very wide range of preferences and tastes.
What may be "consumable" by one, will not be by another.
Not everyone likes green eggs and ham.
What that philosopher should have said, and thought of before hand is this:
"It must be conformed to a specific group of the public to which is applicable to said group that would deem it suitable for their consumption".
The one size fit's all prospective NEVER works. And never will.
RFB
Hi. KDX is "The One Size Broadcasting Station." If you don't like it, what's wrong with you?
Went into storage and brought out the 8-foot grounding rod. My masonry guy thinks he can sink it with his railroad sized slamming-tool (I forget the name of those major hammers)... "pile-driver?"
Ordered a 970kHz crystal. That will be the most open channel if everything tunes up.
Getting prepared to test "neutral injection."
Latest line being planned for a single's bar:
"Hi. Name's Carl, and you'd be impressed by me if you knew anything about carrier current."
"OK RFB. It's almost time for me to ask you those specific questions about retuning the LPB RC-6A. I am almost afraid to do it, because it is working so well on 860 kHz."
Well I would just install the crystal and see if the oscillator runs correctly and stable first and then if it does, move on to the final tuning issue. The only potential roadblock I can see is that damaged tuning cap on the output tank. But maybe it will not have that much effect if it cannot be tuned. Only way to find out is to just try and see what kind of output you get and attempt to peak using the other cap and inductor.
The coupling idea sounds good so I would proceed with that and enclose it into a grounded cabinet to prevent excessive radiation from the home made air toroid coils.
Let the adventure begin! 🙂
RFB
I have, right next to me on the desk, a
crystal for 1020 kHz. This will hopefully
work in my LPB RC-6A. (1020 is the
preferred channel, for a bunch of
reasons, which I think I had mentioned
in a previous post.)
The crystal is in an FT-243 holder. It is
from my very good generous friend.
The rock IS old. It says 1020 KC on the
side.
It will take some time for me to do the following:
1) Make an adapter so the crystal fits in the RC-6A's
larger crystal socket.
2) Test the transmitter into a dummy load and hopefully
tune it up on 1020 kHz with 6 watts out.
3) Build a 10 dB RF attenuator. (For now.) When it is
hooked up to the LPB unit, hopefully about 600 milliwatts
will exit the attenuator output at 50 ohms. This will
isolate the transmitter's RF out from the load. Most
of the RF energy will be used up in the attenuator.
The 600 milliwatts on 1020 kHz will go into a large LC.
This LC used to be a passive AM BC DX loop. It will be
tuned for max.
Then an extension cord will be wrapped around the LC.
It will be plugged into the transmitter and the AC outlet.
The LC will be tuned for max again.
For now, the transmitter will be grounded to a water pipe.
An FM tuner and audio amp feeding the transmitter
will be floating above ground - at least until the transmitter
is grounded. I don't see any problem with this, because
this arrangement will never have any direct connection with
the AC line, as far as I can tell. If anybody thinks I'm wrong -
please let me know. (The AC outlet will be checked to make
sure it is wired correctly.) The FM tuner and audio amp
will provide the DRS2 station programming from the local house
90.9 MHz FM transmitter. This is a weak signal, so
I will be using a SONY HD FM tuner, which is very very
sensitive and selective.
That will be it for this experiment. I don't know if it
will work, but it is worth a try. I can probably get a
commercial coupler on extended loan without any
problem. But I want to try this first.
If you guys have any comments on this, please let
me know.
Best Wishes,
Bruce, DOGGRADIO STUDIO 2
"That will be it for this experiment. I don't know if it will work, but it is worth a try."
A very well planned first home brew CC coupling attempt!
The attenuator, if I correctly interpret the descriptive design parameters, will provide the very low level signal at the output point but further in will slowly in stages work back up to the 6 watt level at the input, all while providing the 50 ohm match for the TX, meaning a low impedance to high impedance 9.6dB attenuator. I see no reason to not proceed!
I suggest running the TX into the dummy load for the initial testing of the new frequency crystal for stability and to ensure the proper loading on the final since it will not be tuned that high in the band, help keep the unit from over stressing the final prior to going
through the attenuator/LC coupler setup.
Look forward to the next stage and report!
RFB
I know you have been busy the
last few days, so thanks for
your comments. AND for backing
up the website comment info.
I'm glad you gave me the green
light on this thing.
There is a lot going on here, so
it will take me a while to get it
going.
My main concern is: will the 1020 KC
crystal work, will it be on channel,
and will the transmitter tune in that
range.
In the not too distant future, I probably
will have some specific questions for you
about 3 components in the transmitter.
They are - the two compression caps you
tune for max, and the tunable inductor -
which has a set screw on it. I think
tuning the inductor so that it has less
inductance will bring the transmitter up
in the band. That means the tuning shaft
will be turned counterclockwise. This is
good, because it is almost all the way
down into the transmitter deck, where the
tubes and other parts sit. (I think - I'll
have to check - it IS fairly far down, anyway.)
The part of the shaft where the screwdriver
is supposed to go is broken, so I'll have to
use a pair of needle nose pliers. No problem
there.
After the inductor is tuned for less inductance,
I guess the trick is to tune the two caps for
max RF out. At least going from 860 to 1020
isn't too far.
It will take me a little time to build the
crystal adapter, and the attenuator.
Wish me luck!
Bruce, DOGGRADIO STUDIO 2
I just reread your last post and
understood some things that I
didn't understand before. So
if MY last post seems a little
lacking in a few areas, well -
I understand things a little bit
better now.
Thanks again,
Bruce,DOGGRADIO STUDIO 2
You never knew I was gone. But this morning after signing into the site, a disaster movie script started to unfold.
The worker who is tuck-pointing my wall pointed out some shaggy roofing tiles that must have been ripped by the high winds a week ago. So I called my roofer and their answering machine took my call, so I would wait for the call back.
Then the internet and telephone went dead so no one could call me, I couldn't call out, KDX was unable to reach the streaming world, and a rain storm was starting.
I drove to my auto service place to use their phone to let the roofers know my phone was broken, then went to the cable office and learned there were multiple outages in the area.
The tuck-pointer drove the 8-foot ground rod into the earth in preparation for carrier current testing with the neutral injection method. The rod went in without hitting rocks or other obstructions.
Five hours after failing, the internet and telephone came back, and I was able to speak with the roofer and that problem will be taken care of.
The cable company called and I thanked them for getting it fixed. She told me that a "fiber had been cut."
This will be a happy carrier current weekend filled with excitement with the possible exception of an approaching asteroid.
Sounds like another plot for the
"LAST MINUTE RADIO THEATURE!"
Bruce, DOGGRADIO STUDIO 2
appeared on one of Carl's Low
Power Hour shows. I might be
spelling it wrong because it's
2:10 AM local time here. Anyway,
I think the show is very very
funny. The Last Minute Radio Theater
Or LMRT, as I like to call it - is
also very short, which makes it funnier,
I think.
I just thought I should explain this,
just in case anybody wondered what the
show is. (It's a show within a show.)
It is now also 2:30 AM local time. Because
of an unusual work schedule here, there is
really no distinct day and night in this
family.
Well, back to the CC stuff. I am going
to be firing up my CC transmitter tomorrow
for some burn-in tests. The other
parts of the plan will come as soon as
I can get them done.
Best Wishes,
Bruce, DOGGRADIO STUDIO 2
The ground rod having been in since yesterday, I mounted a small American flag on the rod so the tuck-pointer wouldn't trip over it, and stood back so he could tuck.
Then at 3 a long lasting storm came along with mighty blasts of lightning delaying everybody's work. Computers shut down for safety.
Now at 5 PM the streaming has been turned back on but the rain keeps dripping, not the right time for electricity work.
See you tomorrow, when carrier current will flow.