I think you have to bypass the amp to receive.
I hear you and that would go with what I’m experiencing but it does not go with the description of the amplifier:
“Transmit Receive Two-Way Power Amplifier”
“AB-915 Series Bi-directional signal amplification module”
“The product is a two-way amplified TDD working mode (that is, the transmit power and receiving sensitivity will be amplified equally)”
That listing is the only place I have seen offering to amplify receiving on Lora, looks like a scam.
Ooh that stinks 
hope not
Anyone any good at looking at the circuitry to see if it even looks like it should be capable of what it states it’s capable of?
For meshtastic you are going to have to bypass it, maybe it works for some other lora case? There do not seem to be any happy real customers on the listing, so that is usually a bad sign.
They did not use circulator for bi-directional, the idea they used is smart but may have some minor problems.
According to your photo, they do used RF switch for controlling RX/TX, however they control the RF switch by using the RF power level(directional coupler or something similar). What if the receive power higher then the TX/RX threshold after RX LNA? This may happen if there are some other 868Mhz to 915Mhz devices around you, and your RX signal chain has some mismatching and reflection. For most RF circuits copied from the reference design, mismatching is likely to occur. Because it is difficult for manufacturers to use the exact same substrate as the reference design.
Ps. according to the photos, there may be some recycled chips in the circuit, which will reduce the yield.
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Thank you very much for your reply this gives me something more technical to reply to the seller with. I tested it with a nano VNA and the odd thing was the rx DB level according to a test I found online got even higher when I powered the thing on.
Hello my name is Dave I read you were successful in getting the 4 watt amplifier working. I bought two of these 4 watt amplifiers and would like one for mobile use and one for stationary use. Unfortunately due to my arthritis and limited eye sight I am unable to build the project myself. Are you open to being paid to help me set up two nodes with the amplifiers?
Dave Pitre
Email me jm@meshtastic.com