A common criticism of 70cms D-Star repeaters is that the input can be somewhat "deaf". This ofter results in a situation where you cannot always access it even though you can hear it on your radio - this is more apparent when using a hand held with low power and inefficient aerials.

The standard fix for this is to retrofit a 70cms preamplifier and a simple filter inside the ID-RP-4000V band module - the one recommended by the RSGB ETCC is the Kuhne Electronic MKU LNA 432 A is retrofitted inside most systems. In our case, this task is not easy with the output being only 1.6MHz away instead of the usual 9MHz and significantly more filtering is required.

For those interested in the details of the preamplifier - the specification is shown below...