The improvement in first if selectivity is dramatic.
Inrad roofing filter.
Installing the inrad roofing filter the mp roofing filter mod consists of a 6 pole 4 khz wide filter followed by a high dynamic range feedback amplifier.
This section allows you to select specific add on features for your particular rig manufacturer.
Please see our document titled a few words about roofing filters for more details.
Able cost using inrad roofing filters.
This mod works in all versions of the yaesu ft 1000mp line of radios.
The amplifier provides enough gain to overcome the filter insertion loss.
The n1 n2 switching cable gets extended and plugged into the inrad board.
Here we take a look at how these inrad filters measure up to their yaesu alternatives.
The icom ic 756proiii roofing filter mod consists of a 6 pole 4 to 5 khz wide filter followed by a high dynamic range feedback amplifier.
Yaesu ft 1000 ft 1000d roofing filter.
Installation is simple and requires soldering the 12v and ground wires.
The plot below shows the sweep frequency response of the rf board in an ic 775 radio.
This roofing filter can help reduce the third order intermodulation from multiple strong signals in the 2 to 20 khz region either side of the tuned frequency.
The amplifier provides enough gain to override the filter insertion loss plus a db or two.
A supplied jumper cable connects back to the if board.
Inrad roofing filters for the ft dx5000 bench results and observations based on an idea from daniel sandu yo3gjc inrad has taken their stock series of 9mhz filters and fitted them to a daughter card allowing drop in use in the yaesu ft dx5000 series rigs.
The plot below shows the sweep frequency response of the front end and first if filter in an ic 756proiii radio.
One coax is moved and a coax jumper is added.
We provide a large selection of options for many different radio manufacturers.
Two coax cables insert the roofing filter between the rf board and the 9 mhz if board.
Select the radio of your choice below to find the filters and or roofing modifications you seek.
The 3oimd response of your receiver can generate an interfering signal s right on top of the one you are listening to from two or more signals outside your lis.
A two screw terminal board connects to 12v and ground.
Inrad roofing filters can substantially reduce the third order intermod from multiple strong signals in the 2 20khz range on either side of the tuned frequency.
A four position dip switch is used to set up the roofing filter function.
Twice another frequency referred to as the third order k f 1 f 2 2 response.
