Thanks Pete et. al., that's about what I thought. But I've decided to be anal about this and "do it right". The splice is Mickey Mouse and I should have used low loss RG-8 type coax in the first place rather than the RG-8/U mini that I installed. Moral of the story: research problem before plugging in soldering gun. [:~)

Whew! I greatly appreciate the replies, but think I've done a poor job of phrasing the question. Steve ended up saying what I should have:

"It seemed to me the correspondant was really asking, by implication, whether it's okay to splice coaxial cable at VHF-UHF frequencies without impacting overall performance. Performance has no direct relationship to reactance...but it does, to 'loss.' "

What I was thinking was that inserting extra couplings in the feedline could change the reactance characteristics of the line CAUSING a decrease in radiated power in the bands for which the the X200A is designed. I was making no guesses what the effect on VSWR would be (the current antenna - a folded monopole - shows 1.1:1 to 1.3:1 across the 2m band).

I'm embarrassed to say that the books I need to read to get smarter on this are in the stack UNDER the ones I'm reading for license upgrade testing next month. Thanks for trying to help me understand what's going on.

I'm replacing a monoband roof-mounted antenna with a Diamond X200A (2m/70cm) this weekend. As it turns out, differences in antenna mounting setup means the existing coax will be about 2 1/2' short. Building a cable extension would easily solve the problem but I seem to remember reading that these "patches" can change the feedline reactance characteristics. Is this a big enough deal to warrant installing a new feedline of proper length?? Any thoughts on this would be appreciated.

Thanks for the tips. The antenna is a folded unipole located at least 25 feet from the PC, so I guess I need to concentrate on trying to get the 60hz choked on the speaker system power and/or or audio cables. I also do have room to move the radio further away from the computer, so will try that. Unfortunately, the office power outlets are on the same circuit, so I'm pretty much screwed there. If all this fails, it's easy enough to switch off the external PC speakers, which instantly cures the problem. A minor annoyance, actually. I Suppose I should be grateful that I'm not entertaining the wife with QSOs on the TV, stereo, etc..  [:~)

I'm using an Icom 2800H hooked to an Alinco 330 power supply as a fixed 2m/70cm rig in my office. The radio and control head are mounted within a foot or so of my PC. The PC speaker system puts out a 60hz hum on tx. This is becoming annoying and I need to resolve the problem. Now for the dumb question: is this the kind of problem that can be cured with ferrous torroids on the radio and PC power leads, or are more aggressive measures likely needed? Thanks for any thoughts on this.

P.S.: along with the hum, a portion of the PC monitor screen closest to the radio "washes out" (as though it were being degaussed) during transmit.

P.P.S.: I've received no reports of unusual noise on the carrier.

This is turning out to be an interesting experience, philosophically. With 15 or 20 minutes of practice every day for about two months, I am very close to actually hearing letters vice dits and dahs when listening to the entire randomized alphabet at 13wpm (still confusing Y and Q). What's interesting about it is that I finally think I understand why some folks cannot learn Morse: It's because they are unable to break through the mind-numbing, gut-wrenching, soul destroying tedium of listening to unmodulated tones over and over and over and over again. (OK, so I tend to exagerate a bit :~)) For those of us who are not lucky enough to pick up the code quickly, that, alas, seems to be what it takes. Which is OK - I thought calculus was easy stuff, so a little humble pie is no doubt good for me. Mercifully, the 5wpm rate used for the test seems agonizingly slow in comparison. By the way, if I had to pass a 20wpm test, I think I'd be grumbling about this slow-code business too. Cheers.

Any of the companies you list make good antennas. I have a Larson 2/70 with NMO mount on my Explorer. For some of the reasons you list, the permanent mount is always a better solution - all other things being equal. But all other things aren't equal, so the question is how much increase in performance and looks is the essentially permanent damage to the vehicle worth to you? In my case, it came down to the fact that I intended to keep the vehicle till it died - or at least to the point where a hole in the roof would be "lost in the noise" as a resale issue. Unless you have a car with a relatively high projected resale value at trade or sell time, I'd drill the hole.

I'm using my 2800H as a base rig and like it. Before you total up the bills on these two radios, however, you may want to consider where you'll be mounting the 2800H in your vehicle. It comes with a dinky standard 3 ft mic cord, which plugs into the radio unit, NOT the control head as does the V7A. Unless you mount the Icom somewhere very close to your driving position, you'll need to buy one of the extended length mic cords (~ 8' or 16' as I recall). FWIW.

At $1500 bucks, think I'll wait on the review too. Without knowing anything else, I think I'm going to wait for the Ten-Tec 526 IF-DSP VHF all-mode to get out of FCC testing and on the market. Even buying an amp to go with it (it's a 20w rig) would bring the price in less than the Icom. Check it out at:

http://www.tentec.com/TT526.htm

Hi Scott. Check out the Premier (Pryme) RD-98. I bought one of these little gems and found it to be a significant improvement over the OEM antenna and one of the telescoping jokes I tried. The antenna is 17" long and flexes like a piece of spaghetti, but works great! Seems like the price is about $24 bucks at HRO (or maybe it's $19, don't remember).

Please do. Besides being a legal requirement, it's just good manners.

Thanks Brian, I may do that yet. Learning to recognize the characters at 13wpm is not what's causing me problems at the moment. It all goes to sh#t when I try to start copying them down. Maybe I should have started on this 30 years ago when I could walk and chew gum at the same time. :~)

Bill, thanks; that's good news. I'm going to set the radio up on a homemade mounting platform for base use. What I need is interface cables about a foot long instead of 6 feet. I was concerned about running into some kind of proprietary connectors which could not easily be modified to suit my setup.

I'm not familiar with the DJ-195, but you also might want to be prepared to buy a bandpass filter if you plan to feed a roof mounted antenna with it. My Icom W32A suffered from horrendous intermod (pagers, NOAA weather radio) problems until I put a bandpass filter in the line - presto, problem gone. FWIW.

I'd like to use this radio as a temporary base rig until the Ten-Tec 526 VHF radio is available. Can anyone tell me what kind of port connections Icom uses for the control head-to-radio interface. I'm not thrilled with the idea of long cables hanging on my shack desk and would like to make short ones myself if this is possible. Ideas greatly appreciated.