Drying wood with chart (Is my wood dry?)

I would like to pass on info I found when I think it might be helpful to others. I would love to get some confirmation that this is a usable chart from someone. I have been taking notations of my woods moisture content lately and found a chart that helps explain the equilibrium of Moisture Content in wood with Relative Humidity of the location it is stored after a time period. Moisture content of wood may be controlled by controlling the Relative Humidity where it is dried. Here is the relationship between relative Humidity (RH) and wood Moisture Content (MC).
58-64 RH – 11% MC
52-58 RH – 10%MC
46-52 RH – 9% MC
39 -46 RH – 8% MC
32 -39 RH – 7% MC
25 -32 RH – 6% MC
19-25 RH – 5% MCTip: Add heat to push the relative humidity lower. For indoor wood use I would like to be lower than 10% to prevent additional wood movement/drying. Check this against your homes humidity levels though. Or just store your wood inside your house for a long time before working with it.

I think Gene Wengert is the source of this chart. Also, I would love to find a time based chart as well. In other words, how long it takes to move +/- a percentage in MC. hit me up if you have something like that.

Now I can go do more of those projects in my honey-do list.

Feeling pretty handy,

cropped-11-21-17-the-handy-hamilton-brand.jpg

 

 

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Wood Spice Drawer

The wife asked me about how she could make it easier for her to see all the spices and get to the ones she wanted easier. A spice drawer on sliding rails is what I came up with. A quick trip to the store and back with the wood I come.

Then I get to cut up my new wood into short strips just large enough to slide in and out of the cabinet. This ended up being 9 inches by 11.5 inches.

Dovetail joints and dado floating drawer seemed perfect for this quick project so away I go.

Hmm, My router killed my first attempt so now we sort out what happened to the router (Ended up being a stripped screw for the position stop). After 3 attempts I sort out what went very wrong and end up needing new wood.

I move to cherry this time but like the oak pictures so kept them… moving on. Finished product, but in cherry wood.

Personally I do not like the dado gap that happens so I might sort out another method next time I do this.

Attached drawer slides and installed.

A happy wife is a happy life.

cropped-11-21-17-the-handy-hamilton-brand.jpg

 

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SMARTsFest in Minnesota – Philco 42-327 revival Part 1

I went to the SMARTsFest a few weekends past and came back with a new project. It is a 1942 Philco 42-327. This is a tube radio and I will be rebuilding it to working order and cleaning it up of course.

Step one, this things needs a good cleaning. After taking the radio out of the chassis I then “dusted” it by blowing compressed air at the chassis and radio itself. This was on a low PSI setting (low pressure) and got much of the junk out. This unfortunately destroyed the paper docs glued inside the chassis because they were so brittle. I did think this would happen and took pictures of them before hand if I got ambitious and decided to recreate them.

Next, I have gone through and recorded all the cap values and they are on the way. I ordered through DikiKey. I figure “why risk it” and will simply replace all of them. Lets hope they come in this week and I can get further movement on this one.

I ordered Gojo from Amazon since finding many internet sources telling me that a Gojo wipedown was a good start to cleaning the wood cabinet. Apparently you take a little Gojo on a rag and wipe lightly all over the wood to clean. Cannot wait to try this out and see how well it works.

Lets check out the before pictures, shall we?

And of course we start to dive into taking it apart…

Hmm, Looks like the glass will need a new print.

To be continued once I replace the capacitors (A must in all these old radios with original caps)

Have fun and 73’s,

Let me know what questions you want me to address or if anything is unclear. My email is k0fey@arrl.net

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DIY Magnetic loop

How it works:

A loop antenna is effectively a tuned RLC circuit. What does this mean? It means the primary coupling loop inductively couples to the secondary. The secondary loop has a variable capacitor to electrically adjust its resonance. Alternatively, Some people use a toroidal transformer, and still others use a gamma match.

The variable capacitor is the biggest decision on the limitations of your antenna. Some folks use a variable capacitor that is smaller and handles low wattage (before arc-over). This would be for QRP (less than a watt) or Shortwave/Ham Radio listening.  Others pick up a costly vacuum variable capacitor (Great for high power since they handle large wattage) and go all out. Keep in mind that an air gap of 1mm equates to a breakdown voltage of about 1KV, which can be encountered when as little as 20 watts is used. A Magnetic loop antenna for 1-5 watts can be made fairly inexpensive.

The circumference of a true magnetic loop should be less than 1/10th wavelength and the coupling loop at 1/5 ratio to the main loop. Here is a great calculator for sorting out lengths, values, etc. You could use a very specific capacitor and not have it variable if you were only staying on a specific frequency, but what fun would that be?

What can it do:

This thing is an amazing easy homebrew project. I can tune by simply listening to noise (for highest volume when tuning) but can also use an SWR meter and can cover multiple bands.

In my testing with my antenna analyzer I found I get 1.5:1 SWR. This is ranging from 5.6Mhz to 8.8Mhz. Now with the Primary Coupling Lop at 4 feet exactly and the Secondary at 18.3 feet I am getting a single ham band. I could actually get 7Mhz – 14Mhz by doing the Primary Coupling Loop at 3.4 feet and the Secondary at 17 feet. I will do this but am enjoying getting some of those ShortWave signals I have never received before.

I live in a townhouse and have “Attic Antennas” exclusively so I need a good multi-band antenna with low SWR.

The build:

18.3 feet of copper pipe and a 2kw variable capacitor….. A nice start to the project and a great excuse to start my magnetic loop build. The Variable capacitor was a gift from another ham in my radio club.

IMG_2641.JPG

I bend the larger copper pipe to form a circle. Then I laid it out to get an idea of what it would look like and start to think about how I wanted to mount it.

IMG_2642.JPG

I laid out the ends onto a board and hammered the ends flat. Then drilled holes into the flat portion for a place to mount the pipe.

IMG_2643.JPG

The variable capacitor has screws on either side so this is a good mounting spot for the secondary ends. I bent the freshly drilled holes up and mounted them directly to the variable capacitor. If this is not possible on your variable capacitor then be sure to keep the connection leads as short as possible.

IMG_2694.JPG

I ran to the store and got a quick 4 feet more of copper pipe so I didn’t have to cut down the 18 feet. I was afraid of losing the 20 meter (7Mhz) band. At first I tried a 20 watt soldering iron with copper tip…. no luck. I ended up having to use a small torch to heat the copper pipe hot enough to take solder.

IMG_2695.JPG

What does this look like all put together?

IMG_2696.JPG

Yeah, OK.. I get it. At 8 feet tall and 4 feet wide, this is not going with to all the hams in the park or meet ups. This will however make it to field day and was a very fun project.

So how would we draw this out:

popeye-aa5tb-loop05.gif

Notes on magnetic loop antennas:

For HF the size is very good compared to a dipole antenna or some others. It is however very directional, which can be good or bad, depending on use.

Also, The magloop does have an Electric field.  It is just not found until you get a bit away from the antenna, my old field strength meter does show an electric field on its little vertical antenna when I get about a half wavelength or more away from the loop.  Inside that, it shows nothing.  But don’t lose track of the fact that a radio wave must have both E and h fields perpendicular to each other in order for the wave to propagate.  This type of antenna just doesn’t seem to have much of the E up close to it.

AA5TB gives us a great view of the antenna radiation pattern in the following diagram.

popeye-aa5tb-more.png

I have heard there are reports of mag loops at 100 watts blistering paint on wood a foot or two away. That said, this article on antenna radiation and fields seems to suggest that that would be not possible.

Warning!!! This does not mean the antenna does not have significant dangers associated. On transmit, mag loops develop very high voltages across the tuning capacitor. At 100 watts, they are in the thousands of volts. Even at QRP power, they may be enough to be dangerous. Exercise care, especially if there are kids or pets around.

 

Main problems with magnetic loops:

They are usually low power (or receive only) since the rating on the variable capacitor must be so high if transmitting above 10 watts.

If you are using this for higher frequencies then the wavelength is shorter. This means the coupling and secondary loop are significantly smaller for something like 2 meters and therefor are more portable and are thus lighter.

Parts List:

Next question would be “What is a reasonable parts list?”

I used:

  • 1 x Variable Capacitor
  • 1 x 8 foot long board
  • 1 x 18 feet of copper refrigerator piping (craigslist for free)
  • 1 x 4 foot copper piping (hardware store for $12)
  • Screws to mount to board
  • Old RG-8 cable with PL-259 end (fun fact – SO259 means socket for a 259 end. PL259 means the plug side of it)
  • Something to mount the copper pipes and cap to the board. (Alternatively you could use PVC piping and zip-ties instead of wood, screws and cable runners)

G4ilo says this is a good parts list  for a more permanent DIY Mag loop build:

  • 250pF single gang variable capacitor with reduction drive
  • Plastic case
  • Self adhesive feet
  • 2 x 4mm gold plated binding posts for the main loop connections
  • 2 x 4mm gold plated spade terminals for the main loop connections
  • 250cm length RG-213 coaxial cable for main loop element
  • RCA (phono) plug and socket for coupling loop input connection
  • BNC socket for coupling loop output connection
  • 50cm insulated wire for coupling loop
  • Length of RG-174 mini coaxial cable for coupling loop
  • N7VE SWR Indicator Kit or similar (see below)
  • 2m white uPVC electrical conduit, for fabricating loop support mast
  • White plastic cup hooks
  • Self adhesive Velcro (hook and eye fabric fastener, from XYL’s sewing box)
  • Large plastic tuning knob
  • White car number plate fixing bolt covers (to cover tuning capacitor fixing screws)
  • Bolt for photographic tripod mount (optional)

Here is yet another build of a mag-loop antenna.

Have fun and 73’s,

Let me know what questions you want me to address or if anything is unclear. My email is k0fey@arrl.net

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New (to me) projects on the bench – Part 3

 

8) EICO Model 221 Vacuum Tube Volt Meter

Whenever I get a new (to me) piece of test equipment that is older than 25 years I always want to look at the capacitors. They are almost surely leaking. I thought about bringing this up on the variac and isolation transformer to test but honestly I was going to replace the caps anyway.

Looking at the meter itself I find it in need of a cleaning but in good shape. First thing is to take it apart and wash/scrub the case. Ah, much better smell now.

 

 

Contact cleaner and a pencil eraser for the switches and potentiometers and we can see they are the original caps.

 

“Online manual for the Eico 221 here”

So there seems to be an issue looking at the schematic. The C2 filter going to ground doesn’t have a value. Apparently they used whatever they had back them so you would find anything from 1-3 microfarads. I used a 2 μF cap and replaced all the other ones as well.

Seems to work like a charm but I do need to build the probe still. The nice thing about this one is the DC probe as a 15 Meg 10% Carbon comp resistor in series. The EICO 221 has a higher than normal ( good thing ! ) input impedance of around 25 Megohms for DC measurements, and about 3 Megohms for AC.

AC and Ohm share their test leads with DC being separated. AC/Ohms probe is simply a piece of wire with a probe tip, no coaxial cable, nothing special, plain old multimeter-type probe with a pin-jack. The ohms scale provides its own power and uses the 6SN7. The AC rectifies the AC to DC and then uses the 6SN7.

eico221a

And here is the after pictures:

 

 

The resistors seem to have tested fine and I will likely replace those when I build the probe itself.

Ah, the finished product (I am going to have to turn that power switch properly):

IMG_2618

Here is what is left:

1) Leader LBO-507A 20MHz Oscilloscope
4) REM Electronics Cathode Recovery and CRT Tester w/ original box 
5) B & K Precision Model 465 CRT Cathode Ray Tester with original manuals
6) Shurite Amperes Meter
7) EICO Model 950A Resistance Capacitance Compactor Bridge Tester 
9) Edwards Signaling Transformer 88-100
10) Vapor Tight Heavy Duty Marine Power Selector Switch 12v 150A/6v 300A Continuous
12) ASI Dynamic Transistor Checker 
14) Louis Marx Model Train Transformer
15) Unknown tester device with old radio bulbs

Have fun and 73’s,

Let me know what questions you want me to address or if anything is unclear. My email is k0fey@arrl.net

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Tecsun 2P3 AM Radio build

Tecsun 2P3 AM Radio Receiver Kit – DIY for Enthusiasts, Built it into a radio case !

Bought from Amazon….

This was a fun build. I love the way it is set up similar to the way old radio projects were. I built this for listening to when camping and use it in the shack at the moment for background music/talk/whatever radio.

Follow the directions and you will do great!

 

Amazon Product Description fills in the what is it:

“The big issue for a DIY transistor radio is how to make it good, the Tecsun 2P3 radio kit is made to fulfill this demand. The 2P3 comes with electronic components such as transistors, resistors, capacitors, radio knobs, and circuit broad. It lets both hobbyist and DIYers to build their own AM radio receiver with a detailed diagram and instructions. From this DIY, you learn many things that a book can not tell you, It tells you how the Resistors and IC works together to make a radio work, Fun to Do It. It is not like any other kits, this kit comes with a radio case that designed for the radio, so after it is assembled , you can use it as radio and put into your pocket. If you like to get a better user’s manual, please click here to get it: http://www.etsy.com/listing/208723987/2p3-assembly-manual-supplement Tecsun 2P3 AM / MW Radio Receiver DIY Kits – MAKE YOUR OWN AM RADIO”

Specs:

AM RADIO Specifications:
Frequency range: 530 kHz ~ 1620 kHz
Power supply: 2 x AA size battery
Sensitivity: < 1mV/m
Max. output: 120mW
Quiescent current: 7mA
Size: approx. 165 x 105 x 29mm
Primary Operation Construction:
Mixing circuit
IF amplifier
Detector
Automatic gain control
Audio amplifier

Component List: – Ceramic capacitors – Polyester capacitors – Electrolytic capacitors – Ceramic filter – Resistors – Detector diode – Diode – Transistor – Speaker wire – Screws – Nuts – Hexagonal screw column standoff – Shield cover – Case – Speaker (1W) – Earphone socket (3.5mm) – Potentiometer – Variable capacitor – Audio amplifier – AM oscillator coil – IF transformers – Magnetic antenna – Battery box – Plastic ribbon – Antenna support – Logo – Circuit board – Tuning knob – Volume knob – Non-conductive screwdriver”

The nice thing is how well it works and how portable it is.

Have fun and 73’s,

Let me know what questions you want me to address or if anything is unclear. My email is k0fey@arrl.net

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40M CW Transmitter QRP Pixie Kit Receiver

Wandering around on Ebay, I found myself looking again at the Pixie QRP morse code transceiver.

I purchased for $15 from seller “19d10recon” and got 2 crystal frequencies to use. Laying out the parts I found I was missing 2 but very quickly received those form the seller. 

IMG_2608

This was a very fast build. Easy once the parts are laid out and great layout.

IMG_2625IMG_2626

 

Here is the schematic and parts list:

Here is the finished project with #D printed case as well.

You might notice a modification I did in the center top of the picture on the board. I loved that I got 2 crystals and this had me thinking…. Perhaps I want some flexibility with my frequency. I decided to put a pin board in to ensure I can use different through hole crystals.

IMG_2697IMG_2698

Have fun and 73’s,

Let me know what questions you want me to address or if anything is unclear. My email is k0fey@arrl.net

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New (to me) projects on the bench – Part 2

Started going through the bench stuff from Craigslist:

2) B & K Precision 177 VTVM Dynascan Vacuum Tube Volt Meter Tester – Works, nothing needed.

3) Superior Electric 3PN 116B Variable Powerstat Auto Transformer 109A 0-140 VAC – Works, nothing needed.

11)Triad N-55M Isolation Transformer 115V-115V 250VA-60hz – Works, nothing needed.

13) Shurite Panel Meter – Cleaning needed

Meter tested in good condition but had something on the plastic front. I easily disassembled the meter and tried to wash the cover in warm water, no luck… then soapy warm water, no luck, then scrubbing pretty hard, no luck.

Well, time to get creative, I have been wanting to try this for a while anyway. Taping off the bottom section, to preserve the “fog” there, I proceeded to wet sand (250 grit) the cover for a few minutes until the sanding was all I saw. This left a dull sand line and then I proceeded to use 600 Grit and then 1000 and 2000 to get to a dull fine finish. I would estimate I did around 5 minutes of sanding with each grit rinsing every few minutes.

Then I polished with tooth paste. Yes, toothpaste. I used a paper towel and a dab of tooth paste and rubbed for about 5 minutes and this brought back the clearness. You can see the final result.

Reassemble and pop this one on the shelf to use later.

 

Here is what is left:

1) Leader LBO-507A 20MHz Oscilloscope
4) REM Electronics Cathode Recovery and CRT Tester w/ original box 
5) B & K Precision Model 465 CRT Cathode Ray Tester with original manuals
6) Shurite Amperes Meter
7) EICO Model 950A Resistance Capacitance Compactor Bridge Tester 
8) EICO Model 221 Vacuum Tube Volt Meter
9) Edwards Signaling Transformer 88-100
10) Vapor Tight Heavy Duty Marine Power Selector Switch 12v 150A/6v 300A Continuous
12) ASI Dynamic Transistor Checker 
14) Louis Marx Model Train Transformer
15) Unknown tester device with old radio bulbs

Have fun and 73’s,

Let me know what questions you want me to address or if anything is unclear. My email is k0fey@arrl.net

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New (to me) projects on the bench

I was looking through Craigslist and found a few things that will go into the repair bin. Will tackle these one at a time in the next few weeks. (I hope)

1) Leader LBO-507A 20MHz Oscilloscope
2) B & K Precision 177 VTVM Dynascan Vacuum Tube Volt Meter Tester
3) Superior Electric 3PN 116B Variable Powerstat Auto Transformer 109A 0-140 VAC
4) REM Electronics Cathode Recovery and CRT Tester w/ original box 
5) B & K Precision Model 465 CRT Cathode Ray Tester with original manuals
6) Shurite Amperes Meter
7) EICO Model 950A Resistance Capacitance Compactor Bridge Tester 
8) EICO Model 221 Vacuum Tube Volt Meter
9) Edwards Signaling Transformer 88-100
10) Vapor Tight Heavy Duty Marine Power Selector Switch 12v 150A/6v 300A Continous
11)Triad N-55M Isolation Transformer 115V-115V 250VA-60hz
12) ASI Dynamic Transistor Checker 
13) Shurite Panel Meter
14) Louis Marx Model Train Transformer
15) Unknown tester device with old radio bulbs

 

 

Have fun and 73’s,

Let me know what questions you want me to address or if anything is unclear. My email is k0fey@arrl.net

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Tuning antennas for SWR

Tuning antennas for SWR

**Note: This method is that in which you will be cutting your antenna to ensure a resonant length.

Introduction: Common models of SWR (standing wave ratio) meters are used to give a general reference of how well an antenna is matched to a transmitter. It also has a very simple un-tuned field strength meter that utilizes a diode detector feeding the meter. It’s very insensitive.

So, you’ve put your radio into where you think it will live for a bit, you’ve got your antenna connected and have mounted it somewhere that may even have a decent ground plane. Everything is connected and ready to go, right? Wrong. It’s vital that you tune your antenna before using radio. If you’re not familiar with SWR or the necessity of adjusting you antenna to get a good reading, let us give you fair warning: improper tuning of your antenna has the potential to cause much worse than a weak broadcast signal…. it can end the life of your radio before you can enjoy it.

This article will walk you through the process of properly tuning your antenna (a.k.a., adjusting the SWR). It’s not a terribly difficult process, as long as you can follow directions and are patient enough for a little trial-and-error. Assuming that everything else in your system is properly installed, the only additional equipment necessary is a short length of coaxial cable (known as a jumper lead), an SWR meter, and something on which to record your readings.

The antenna matching unit, or antenna tuning unit, is designed to match a non 50 Ohm antenna to a 50 Ohm transmitter. When used, the SWR meter is connected between the transmitter and the matching unit and provides an indication of the SWR as the ATU/matching unit is tuned to the correct settings. Depending upon the design of the ATU/matching unit, it will either bring antenna into resonance or will just make the antenna look like it is the correct impedance without improving its resonance. We will not be using an antenna matching unit. This is instruction for those without an antenna matching unit. An antenna matching unit may also be referred to as an “Antenna Tuner”.

swr

Equipment needed: Transceiver (UHF, VHF, HF or CB radio), Antenna, Antenna coax, SWR meter, short jumper coax ~3 foot.

Procedure:   The SWR meter needs to be placed in line between the antenna and the transceiver. Connect the antenna (normally connected to the back of the radio) to the connector marked “Antenna” or “Ant” on your SWR Meter. Connect one end of the short jumper coax to the “transmit” or “Xmit” on the SWR meter. Connect the other end of your jumper coax to the transceiver.

Assuming you have a standard SWR meter the switches should read as follows: REF or SWR, FWD, and there should be a slide switch, or dial, marked “set”, “Cal”, “Calibrate” or “Adjust”. If different, be sure to consult your SWR meter’s owner’s manual.

As an SWR meter it is used as follows:

  1. Connect transmitter to SWR meter. (Use the jumper lead to connect your radio and the SWR meter through the connection marked “transmitter” or “XMIT.”)
  2. Connect Antenna to SWR meter. (If reviewing an already installed radio, disconnect the coaxial cable from the back of the radio. Reconnect this end of the cable, which is going to the antenna, to the SWR meter in the connector marked “antenna” or “ANT.”)
  3. Set variable control fully CCW (Counter Clock-Wise)
  4. Set Switch to FWD
  5. Switch on Transmitter and transmit on the lowest power that provides a reading on the meter. This protects the transmitter PA stage. (Remember, throughout this process it’s important to keep the microphone the same distance from the meter for each test.)
  6. Adjust the variable control to provide a reading in line with the calibration point. (Turn the knob on the SWR meter labeled “set”, “Cal”, “Calibrate” or “Adjust” until the needle reaches the setting position at the end of its range.)
  7. Stop transmitting.
  8. Without adjusting anything, set the switch to the REV position. (Now you are ready to measure the SWR on a few different frequencies.)
  9. Transmit again.
  10. Take a reading of the SWR on the meter.
  11. Record the reading given by your SWR meter and release the transmit key on your microphone. (Switch off the transmitter.)
  12. You are now going to repeat this process for additional frequencies. Follow steps 4 through 9.

How to read your results: 

The SWR reading shows the match of the antenna compared to 50 Ohms (The radio antenna input is normally 50 Ohms).

If SWR on the frequency tested is below 2.0, your radio can be operated safely.

If SWR on all channels is above 2.0 but not in the “red zone” (normally over 3.0), you may be experiencing coaxial cable reaction (bad quality, wrong length, etc.), insufficient ground plane, or have an ungrounded antenna mount.

If SWR is in the “red zone” on all channels, you probably have an electrical short in your coax connectors, or your mounting stud was installed incorrectly and is shorted. Do not operate your radio until the problem is found, serious damage can occur to your radio.

If SWR on the lowest frequency is higher than it is on the highest channel, your antenna system appears to be electrically short. Your antenna length may need to be increased.

If the SWR on the highest frequency is greater than that on the lowest, your antenna is considered to be “LONG” and reduction of physical height and/or conductor length will correct this situation.

The objective behind tuning your antenna is to make these two readings (Top and Bottom of the band) as close as possible. Getting down to a 1.5:1 ratio or below makes for a passable broadcast signal. Here is an example to help you understand before adjusting the length of your antenna:

               If the SWR on 14.280 Mhz is higher than that on 14.100 Mhz, your antenna is too long.

               If the SWR on 14.100 Mhz is higher than that on 14.280 Mhz, your antenna is too short.

If your antenna is too long, it is necessary to reduce its physical length. There are several methods for shortening an antenna which vary by manufacturer. Consult your owner’s manual for detailed instructions on how to shorten your antenna. While many antennas feature a “tunable tip” that uses a small screw, some antennas may need to be cut to be shortened. Do so in 1/4″ increments and then get new readings to determine your progress.

If your antenna is too short, it is necessary to increase its physical length. Most instances where the antenna length is too short are caused by a lack of ground plane. In modern antennas, there’s usually a method for adding length built in to the antenna. Other options, such as adding a spring, are also legitimate.

Dual antenna installations: If you’re tuning dual antennas, you’ll want to adjust both antennas the same amount each time. As a starting point, it’s best to put the tuning screw either all the way in or out, so each antenna is the same length. Then, based on your SWR readings, length or shorten BOTH antennas the same amount each time. Re-measure SWR and continue to re-adjust as with a single antenna, making sure to make incremental changes that are as close as possible to both antennas.

Readings on both channels that are less than 2.0 mean that your radio is safe to operate, but transmission may not be optimal. If readings on these channels are in the red zone on your SWR meter or above 3.0, do not attempt to use your radio. This problem must be remedied before attempting to use your radio.

Troubleshooting: Let’s review the most common problems that cause your SWR meter to register danger on all channels: poor grounds, a short in the coaxial connectors, or an improperly installed mounting stud.

  1. Vehicle installations: A large percentage of high SWR readings are caused by ground plane problems. It’s a good idea to run ground straps from the body of your vehicle to the frame, doors, and trunk. Running the shortest possible ground strap from the antenna to the chassis or your vehicle is generally a good solution for ground plane problems. Simply put, grounding everything that can be ground together will improve ground plane.
  2. Vehicle installations: It is essential that your mount is properly grounded. Most improperly grounded mounts are connected to places on your vehicle that themselves are not thoroughly grounded. Any part of your vehicle that has a plastic or nylon bushing separating it from the chassis is probably not grounded. Also, chassis paint can often prevent a mount from being properly grounded. You can check the grounding of suspect parts with a voltage meter.
  3. A short in the coaxial connectors may also be the culprit behind abnormally high SWR readings. Issues with the coaxial cables are often identifiable by eye, such as severe bends or pinches. You should know that it’s essential to use 50-ohm coax for single antennas and 75-ohm for dual. When all else fails, sometimes it’s necessary to replace the coax cable because there’s a failure inside the line.

By following the steps outlined in this article, you should be able to successfully tune your antenna for optimal performance and transmission.

Have fun and 73’s,

Let me know what questions you want me to address or if anything is unclear. My email is k0fey@arrl.net

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