Re: Isolator vs intermod panel? The basic difference... a common Intermod Panel is often considered a complete or mostly complete hardware assembly, which (in the Land Mobile Radio World) should include one or more isolator or circulator devices. A single Isolator unit can be a one or dual port device... so the number and combination of isolator/circulator devices used can vary to obtain a more common desired dual port function. i.e. a quantity of two single port isolators placed in series versus one dual port device.
A typical Land Mobile Radio Intermod panel will have one or two isolators trailed by a low pass filter and the rejection ports have proper size 50 ohm terminations (dummy load). Newer IMD Panels often have RF Sample Ports included on the 50 ohm terminations. Some IMD Panels might include metering sample functions. Typical Land Mobile (Two-way) Radio IMD Panels don't have on- board cavity filters. One or more Band Pass Cavities are placed on/after the IMD Panel output connection. ***** A single Isolator is just the "RF Check Valve" device often seen as a stand alone part (but often includes one or two screw on 50 ohm terminations. One will often see an Isolator connected to a trailing Low Pass Filter, which is good practice but not written in stone as a must have addition. Each case differs so some of you should not start jumping up and down about Low Pass Filters being a "must have". As many hams do... I used to squeak by without Isolators and IMD Panels. After a number of lucky breaks and train wrecks I now include them to fault protect the RF Power Amplifier and Receiver. I see them being sold fairly cheap on Ebay. cheers, s. > Paul Kelley N1BUG <paul.kelley.n1...@...> wrote: > > I guess I was lucky in my first few years as a repeater owner. > Lately I have nothing but grief in many forms. (Yeah I know, welcome > to the real world!) > > Can someone tell me in basic terms what is the difference between an > isolator and an intermod suppression panel which contains an isolator? > > If one has a high power tube PA on a repeater, I assume he would > need to use a high power isolator or intermod panel after the PA? Or > would it be sufficient to use a lower power one between the solid > state exciter and tube PA? > > Thanks... > > Paul N1BUG >
