[8525, TyTN, MDA Vario II, JasJam Software Upgradin] jpogge:
I ordered the antenna chips today, 4 anyway, and I found a realy nice self matching SAW filter with a phenominal 2.4 MHz band width, There is a rejection of out of band signals very near 75db. I dont beleive there are export restrictions but I will find out, Either way my plan is to cut a smal RF PCB on our circuit router, and mount the components with a 5", 125mm RG188u mini coax cable. I will test the antenna on a sirf III board I have running on my desk and provide some Spectrum analyzer plots of the received signals.

The dimensions of the assembly will be about 14 mm x 4mm x 2mm, not including the cable which will be soldered on the board. The field lobes are good as well so this should actually out perform the trinity antenna, I would imagine it should be mounted parallel to the GSM antenna preferebly on part of the top of the PCB without a ground as shown in the picture, I would suggest that it be mounted with a small spot of silicone RTV, this holds well, is easily removed and not subject to temeprature extremes.

Right now the wait is on actually getting the parts, when I have them I will build , test and post specs on what I find, after that I will provide 1 or 2 to whom ever is willing to give it a go, I would suggest one of the senior members who has or knows someone with the necessary skills. This is not major , but will be a warranty busting surgery on your phone. If this is the solution, unfortunately it will not be one that a non technician will be able to easily make, soldering .2mm pads is like brain surgery, I would hope there are some engineer / techs out there willing to help..

Basically I envision the following as an example proceedure

1) hermes disassembly,

2) removal of the RF shield cover,

3) after the cover is removed , drilling a small hole in the cover no more than 1.5mm at or very near the RFR 6250 location, and atleast 5 ft from your disassembled phone as metal filings are killer.

4) threading the coax through the hole, the coax is <1mm diameter

5) cutting and stripping the coax to fit, do not curl it up it would act as an antenna for the other signals.

6) soldering the shield wire of the coax to gnd, (the shield cover will do nicely.)

7) solder the tinned center conductor to a resistor connected to or the actual input pin of the pre LNA

8) replace the shield cover

9) silicone RTV the hole/coax in the cover and a small bead between the antenna and the PCB

and the hardest part wait 1 hour for the RTV to set up before reassembly and testing, if the antenna shifts due to not being glued down it might cause reception problems.

For now we still need photos of the trinity and the RFR 6250 to identify the input pin of the LNA. This assembly will be benign and very passive so if the user is properly grounded it will not hurt the device at all.

A plumbing disater has postponed my purchase for at least 2 months, or I would do this myself, If we dont have the info I might just buy the Trinity and find out what the pin is myself after that I will provide any info and findings to the volunteer, Im not giving up on the hermes, just being practical as I cant afford both right now.

If this works we can talk about finding someone who can kit this up....