ARRL

WD6EJN

Joined: Sat, Apr 4th 1998, 00:00 Roles: N/A Moderates: N/A

Latest Topics

Topic Created Posts Views Last Activity
Neighborhood Net Feb 4th, 01:23 1 132 on 4/2/14
Alinco DJC4T 70 cm credit card radio docking stations Aug 7th 2013, 21:26 1 312 on 7/8/13
mast mounted bi-amp Jun 10th 2013, 23:17 3 319 on 18/6/13
TV TWINLEAD CLAW SCREWS Mar 26th 2013, 23:21 2 466 on 10/6/13

Latest Posts

Topic Author Posted On
Neighborhood Net WD6EJN on 4/2/14
I would like to start an EOC type communication network that just goes around the block, I have tried to have neighbors use their own frs/gmrs walkie talkies with no luck and I have no money to buy units and donate them.
I am looking for dirt cheap below $5.00 (surplus) 400-mhz to 1.2ghz (part 15) fm transmitter kits that I might provide as a project or I might build them, wireless microphones seem to be very expensive and always include a recever at additional cost, where can I find extra wireless microphones without the receiver.
I wonder if there is any way to convert a blue tooth to analog or am?. I already have receivers so I don't need included receivers.
I heard a ham in Oceanside talking on the local repeater (13/73) in a retirement community describe his eoc where non-hams use a repeater! I wish I wrote his call, this does not sound legal, I can only assume it was gmrs.
I found these tiny transmitters but it would cost me more to design the circuitry to fm modulate, and with a fet preamp to get more power.
Don't like the frequency for fm, wonder if I can modify for 447 simplex also everyone would have to have ham licenses.
How does one convert these to frs/gmrs?
When I was a kid and first got my license, I built a two meter fm transmitter, it was quite easy to modulate using a varactor/varacap diode, perhaps I could do this.


RF Link Transmitter - 434MHz
WRL-10534
Description: These wireless transmitters work with our 434MHz receivers. They can easily fit into a breadboard and work well with microcontrollers to create a very simple
Alinco DJC4T 70 cm credit card radio docking stations WD6EJN on 7/8/13
Where can I find these?
I would swap antique parts for these even if they don't work!
I want to mount them to the wall like a phone.
mast mounted bi-amp WD6EJN on 18/6/13
Oh I know I should have thought of some of the collector to emitter circuits I built (following instructions!) using so many turns and studied the plate b+ circuits in ham school many years ago, but had to post this to remember!
Now I have another issue...I'm using a coax balun at the ham rig and it shows a shunt, I am hesitant to use capacitor blocking.

I think about if I just had the bi-amp picking up the rf much like a high impedance test probe, I could transmit enough energy at the shack to power the circuit, of course I would have to run some power to charge a battery defeating the purpose of running high current dc in the first place.
Actually I don't really need extra power for transmit even if the loss is so great that it becomes almost a part 15 device! it's more about the receive amp, although with twin lead, the reasons for using coax and cutting down on harmonics makes using antenna mounted amp a must.
TV TWINLEAD CLAW SCREWS WD6EJN on 10/6/13
Quote by WD6EJN
I'm building a hidden antenna using old fashion tv twinlead, the kind one used to find in any hardware store.
Now that I found a length, I don't know where to find those splitter boxes with the claw screws, everything is f-connector now.
Somewhere near Carlsbad California would be nice since I don't have a car.
Still looking for a box of these things! kinda useless without them.
If you saw my previous post, I'm planning to have an antenna desquised as a kite line (white) but I have to run tv twinlead to it, I found some at Fry's although the loss appears to be around 20 or 30 db! I don't care as I just need the super lightness.
I can always have a pre-amp for the receiver or just transmit and listen on an indoor antenna even if the power in is 20 watts in 1 watt out.
There are plenty of old fashion tv cable to twinlead balun/conv around, but I would have to canabalize these to get the claw washers, and this is too expensive for me.



Follow-up:
I was able to use those taps that they use for automotive (non-critical connections radios/amps etc.) I used red 22 gage and ended up soldering the connections and discarding (in junk box,,it's impossible to through things like these away).
The twinlead from Fry's is impossible to work with.
mast mounted bi-amp WD6EJN on 10/6/13
I am having my antenna a great distance from my ham rig as I have posted many times on this site (kite in tree).
I will be mast mounting the bi-amp some distance from my ham rig and using 300ohm #22 gauge open wire feeder for stealth (white wire appears as kite string!)
I need to find the values of chokes to power the circuit and estimate it will draw about 4 or 5 amps.
Just by common sense I would pick the highest inductance depending on the lowest frequency hopefully 10-80 mhz and the gauge of wire wound would be approximately 16 gauge, weight is critical.
How is this going to effect the impedance of the open wire? which seems to be almost impossible to find sometimes (tap).
I'm afraid the chokes will simply raise the impedance too high or act as load and drop to short.

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