As I was faced with the numerous e-mails asking for the UP-100 and later UP-125 that we stop to sell (we do have just the blank PCBs), due to the fact that there is an amplifier included in the design we decide to help all this guys this way.
Most of them already have the various upconverters where the reception using the simple peace of wire antenna is weak. We also receive requests to modify their upconverters in order to improve overall characteristics. This LNA4HF may be the simplest solution for all of them, including the guys using direct sampling method.
There is the 5 pole 30MHz cutoff low pass filter included in the amplifier design cutting the commercial TV and radio broadcast bands from saturating the upconverters and dongles.
The PCB is designed to accommodate also the other types of mmics where the same board can be also used to amplify the transmitting signal from the various sdr boards.
Various setups are possible.
The "pay later" approach is applied just because most of the guys are happy with that. They receive, test and at the end pay ordered. If they do not like the product, they can return it back.
If there is any question regarding the LNA4HF please post it, I will be glad to answer on all technical details I know.
At the end, here is the resent photo of the machine assembled batch of LNA4HF.