I second Jeff's comments. The 8920A/B series are much better than almost all IFR monitors, with the exception being the COM120B. To put it in simple terms, the HP 8920 is the Cadillac of monitors, while the COM120B is the Mercedes.
I've owned a Motorola 2670A, an HP 8920A, and an IFR COM120B. The 120B is by far the best service monitor. It is the most flexible, especially when setting up repeater links and multiple-banded systems. It also has an excellent analyzer and oscilloscope function. But when they break, be prepared to be raped by IFR/Aeroflex. Either them or nobody. Just try finding tech docs on the web for an IFR. On the other hand, the HP tech docs are easily found on Agilent's web site, among other places, and there are many folks like Amtronix who are happy to sell you a replacement module, or repair your unit for you at reasonable rates. I'll give you a prime example- one of my field tech's COM120B recently died. Sent it to Aeroflex. Bad power supply, and a few other minor issues. They wanted almost $4k to repair it. I called and spoke to their supervisor, in an attempt to have him justify the high cost. In so many words, I told them to keep it, and turned around and bought my tech a clean loaded HP 8920A for around $2500. And even that price was high, as I bought it with a recent calibration and decent warranty from a reputable equipment broker. But for ham use, there have been some awesome deals on eBay lately. I've seen decent well-equipped 8920As (HS,signaling, tracking gen, etc) going for $1500 or less. And 8920Bs are going for less than $2500 at times. Don't worry too much about a unit having recent calibration - I've compared units last calibrated in 1999 against recently calibrated units (including a brand new GD unit) and they were all close enough for simulcast work. Not enought to justify calibration costs for most work. The secret is to not be in a rush - check eBay regularly, and you'll find a decent HP every now and then. Or if the budget allows, you can regularly find a nice IFR COM120B for around $3-4k (depending on options). With the current economy and job market, the prices on test equipment has eroded greatly in recent months. Eric KE2D --- In Repeater-Builder@yahoogroups.com, "Jeff DePolo" <j...@...> wrote: > > > I'd be leaning toward an HP. Even if you have to pay a little more up > front, you'll come out ahead of the game in the long run. I have three HP's > (two 8920B's and an 8921A, with various options), and in the last ten years > or so, only once have I had to get one of them repaired (spectrum analyzer > self-test wasn't passing). > > Up until fairly recently I also had an IFR 1500 (I think I got it in 1993 or > thereabouts). While I loved the 1500 in my regards, it became too expensive > to continue to repair. The death knell for it was when the CRT died (the > original CRT's are NLA, Aeroflex wanted something like $2200 to install a > different CRT and replace the power supply with a different type that was > compatible with the new CRT). Thanks but no thanks... > > Unless they're abused, the HP's require little maintenance. I check the > reference oscillator every few months (using a rubidium standard), and it's > always right on, usually less than one Hertz error when generating a carrier > at 500 MHz (all of my HP's have the 001 high-stab option; I can't comment on > the standard oscillator). I usually send them in about every two years for > calibration just so I can sleep at night, but usually no adjustments are > required to pass cal. > > To summarize, keep in mind repair costs when making a decision, as repair > and cal are unavoidable costs, so choose a unit that is affordable not only > today but through its expected lifespan as well. You might call a few > reputable repair outfits and/or the manufacturers and ask about calibration > costs, maybe get a price on replacing a power supply or CRT, etc. just to > get a feel for what you might expect for each of the models you're > considering. > > I've owned or used other IFR's, Motorolas, Cushmans, and the Ramsey. I'll > stick with HP. To quote Dave Karr, "they just work". > > I highly recommend Amtronix for HP repairs and sales. Rick at Amtronix is > top notch and his repair rates are quite reasonable. He also has a good > stock of spare parts, both new and used. > > --- Jeff WN3A > > > > -----Original Message----- > > From: Repeater-Builder@yahoogroups.com > > [mailto:repeater-buil...@yahoogroups.com] On Behalf Of > > kt...@... > > Sent: Monday, July 13, 2009 9:46 PM > > To: Repeater-Builder@yahoogroups.com > > Subject: [Repeater-Builder] Re: Service Monitor Question > > > > > > > > Thanks for the responses so far. I didn't mean to incide a > > war over this, but the going rate for an IFR 1200S is around > > $4,000 - the reason I'm looking for a less expensive option. > > > > If anyone can speak about Cushman monitors (the 4000) I have > > a lead on one of those. Otherwise, I'll try my luck going up > > the ladder. > > > > FWIW, I do have shop experience with both IFR and Moto boxes > > from years ago; just don't have access anymore or deep > > pockets to play with. > > > > Tony > > > > --- In Repeater-Builder@yahoogroups.com > > <mailto:Repeater-Builder%40yahoogroups.com> , Tony KT9AC > > <kt9ac@> wrote: > > > > > > Hi Everyone, > > > I'm thinking about buying a used service monitor for > > various projects, > > > and I've come across a few units that look good (from a > > price point) but > > > I can't find any data on them. > > > > > > 1) Racal Dana 6113G Digital Radio Test Set Service Monitor > > > 2) Cushman CE-4000 > > > 3) HP 8924C > > > 4) Ramsey COM3 > > > > > > I realize these are NOT the preferred field service units > > (I like IFR > > > myself), but for now I just want something usable here and there. > > > Opinions on them are welcome or pros/cons. > > > > > > Thanks! > > > Tony > > > > > > > > > > > > > > > Checked by AVG - www.avg.com > > Version: 8.5.375 / Virus Database: 270.13.12/2235 - Release > > Date: 07/13/09 05:56:00 > > > > > > >
