Hi Cort, Just something to keep in mind... You can use a regular radio as a signal generator just as you can use another for your receiver/detector function.
Duplexer adjustment is more easily done with some RF-Pads (attenuators) placed on each coax port. I use some 3dB pads fairly easy to purchase off Ebay cheap enough. There are even some very nice low power step and variable attenuators found (on Ebay) for more than fair prices. I've even built basic 1 and 3dB pads from common values found in ARRL and similar Handbooks. Only a few resistors, a proper size box/tube (with connectors) and the time to construct them right... There's also a step attenuator in some ARRL Handbooks and FAR Circuits probably still sells the pc-board kit to make them. So... one might assume your portable radio has a low power output setting, which should be still be more than enough generated signal to see with your receiver. The key to all of this is to at all costs avoid transmitting anything more than a very low (fractional) power signal toward the receiver. Using enough of the right size series placed RF-Pads should be the trick. One "days of old when knights were bold" trick was to solder a very low value fuse inside with a 3dB constructed RF-Pad. Easy enough to replace a 1/8 or 1/16th amp fuse versus the front end of an early Service Monitor Output Section. Many a smart radio service shop had external RF-Pad boxes (with internal pico fuses) in series with the coax from the Service Monitor Signal Generator Port. One other thought might be to find/buy/borrow a small amplifier for your Service Monitor, which would be something like a Mini Circuits wide-band box. Once again cheap enough if you search Ebay at the right time & place. Many things are possible chow for now... s. > Cort Buffington <[EMAIL PROTECTED]> wrote: > Thanks Skipp025! > > I have an old Lampkin service monitor and I've been tuning the > duplexer by using my handheld as a receiver with the Lampkin as the > generator. It just doesn't have enough oomph for proper tuning of the > reject portion of 2 cans in series.... So I'm working "somewhere" in > the notch... not good enough. I'll be looking for use of a proper > service monitor, and probably keep using the MSR2000 unit -- it fits > my installation better than the Wacom.
