What would you use to score the sheet metal? (I'm a bit mechanically challenged.)

Also, are these hand held electric shears (that cut out a thin strip) any good? Can they cut a resonably straight line?

ND9B

Who's a supplier of boxes/chassis/enclosures? I used to buy that kind of stuff at hamfests, but can't find them anymore.

ND9B

I would like to make my own custom chassis and enclosures up to around 18" on a side. What tools do I need to do a good job? (I take it that I'll need a brake and shear.) I see Eastwood has an inexpensive 18" brake. It looks like the sheet metal is held down by a "bar" with C-clamps during the bending process. This does not look like it would allow bends on adjacent edges. Can this be remedied by a short "bar" that fits between the bends on opposite edges?

Now, what about cutting the sheetmetal? I have a saber saw that can cut sheetmetal, but it would make for a ragged, wavy, ugly edge! What do I need to make a nice, straight, clean edge?

ND9B

We had a big ice storm that took down my big Alpha-Delta DX LB Plus dipole a couple days ago. I finally was able to go out today and do a failure analysis. My antenna was supported by a pulley from a side arm off the top of my 80 ft tower. Neither the rope nor the pulley failed. What failed was a stainless steel hose clamp I used to fasten the pulley to the side arm. Now I'm wondering what I should use to fasten the pulley again. Evidently hose clamps don't cut it! Anyone have a recommendation?

ND9B

We had an ice storm last night and my heavy Alfa-Delta fan dipole fell down. The nylon pulley rope suspending the middle of the dipole broke. It's a long way up that 80 ft. tower, especially in the cold! I need rope which will not break or rot. What's my best bet?

BTW, what do you think of plastic clothesline rope? I've never seen this stuff break, and it doesn't seem to chafe in the trees.

ND9B

Has anyone done a mod on this microphone to run the LEDs on 12V ? This microphone is so good looking with the LEDs lit up. But the 48 volt phantom power is so inconvenient for us Hams.

ND9B

I've decided to try a boom microphone. I think it would help free up some desk space, and position the mic for my most comfortable sitting position. I will use it with an Icom IC-756ProIII. I'm in this hobby for the duration, so I'm looking for quality, durable items. Heil seems to be the only brand in the catalogs, and I see good reviews on the PR-781 microphone and the PL-2T boom. Would this be a good choice? Any other recommendations?

I see Heil has an Icom cable. How is T/R switching handled? I definitely want a locking transmit button/switch within easy reach (not the transmit button on the rig). Is there a pig tail on the cable for a switch? I spend hours on nets, and comfort is paramount.

ND9B

Any insight on this, anyone? Are RF power transistors really that expensive? Are we being ripped off? (The 1KW solid state jobs are super expensive.)

Also, why do the solid state linears always require an expensive external power supply? Tube amp designers don't seem to have any problem putting the power supply inside.

ND9B

There must be a simple way of estimating VHF communication range. When I consult the literature, I always run into "path loss", then things get way too complicated, and I never get an answer. Surely two way radio installers must have some tables or guide lines that tell them how high a customer's tower needs to be.

My particular situation is an 80 ft tower, a 50W 2M FM rig, and a 6dB omni-directional antenna. What range should I expect to a mobil? What range to another base with an identical setup? What range to a handitalkie?

ND9B

I always tune up with low power, 10 watts into the amp (this is done automatically with my MFJ-998 tuner). At 10 watts the SWR reads a perfect 1:1, but with full power the SWR shifts up to 1.5 or so. This isn't particularly a problem, but what is changing between low and high power?

ND9B

I have the MFJ-998 tuner and have used it with an Ameritron AL-80B for years (and recently with a Heathkit SB-1000). With the proper harness interface, the "TUNER" button on your rig will put your amplifier in standby, and tune up in less than a second. I'm very happy with it. Be sure to thoroughly read the manual. There are a ton of options to set up.

ONE THING TO WATCH FOR - The "ANTENNA-1" SO-239 output is directly connected to the "WIRE" output. The "WIRE" output is a big wing nut that sticks out of the back on a ceramic post. So the "WIRE" output has full RF voltage exposed when antenna-1 is selected. I don't use the "WIRE" output, so I disconnected it inside the unit. That way, I won't get an RF short with all the ground straps I have running behind the tuner. (Also, I won't get an RF burn if I happen to get my hand back there.)

ND9B

Use RG8x foam, just to be on the safe side. Foam coax has higher ratings than solid.

ND9B

Not many of my ham friends have heard of this model. Is it very rare? I had to wait a long time for one to show up on eBay. I've heard that it is the same as the Ameritron AL-80A, and very similar to the Ameritron AL-80B. Is this correct?

ND9B

Now the amplifier is working with both rigs. Go figure. I made some contacts at full power on 160, 80 and 20M today with no problems. I figure the previous owner must have rewound the plate choke and used the RTV to hold the windings in place. Perhaps the original winding burnt up.

ND9B
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The rig the amp didn't work with was an Icom-756 Pro III. The rig the amp always worked with is a Kenwood TS-570. I just remembered that before trying the Icom the second time (when it worked), I had installed a transient suppresion diode on the coil of the T/R relay. I wonder if spikes from the relay coil were causing a problem in the Icom. 

ND9B

Now the amplifier is working with both rigs. Go figure. I made some contacts at full power on 160, 80 and 20M today with no problems. I figure the previous owner must have rewound the plate choke and used the RTV to hold the windings in place. Perhaps the original winding burnt up.

ND9B