Communications team meeting/workshop at PSBA
Andrew G., Glenn L., Dave C., Dan K., Nathan B.
Talked about routing the board that holds the copper components of the CPA.
- Vacuum table to hold material in place.
- Can't get sharp edges because bit is round. Tapered bit will cause multi radii on the trace.
- 80 watt laser won't cut metal.
- Laser could cut a mask that could be used to expose etch resist, and we could do our own etch.
- If etch ourselves, edges are not precise, and pitted surface is common.
- Could peel away large portions of Cu to reduce routing work if chose that approach.
Talked about alternate structures.
//117.4 ohm -> 58.7 ohm -- first level allows us to skip the first transformer. This was in the 5.8 GHz CPA as currently designed, but Andrew thinks that was an unintentional mistake. Seems like a good idea because it removes one bandwidth restricting transformer from the cascade.
Let's do it again at the second level since it is a tight fit, and it's hard to get the 5h separation of transmission line between the transformer. Let's see what that looks like. //58.7 ohm -> 29.35 ohm -- Yikes! Here's the problem; the width is 401 mils! That's fat!
Glenn drew up a quick sketch of what this would look like. Scanned and emailed? Andrew has original.
- Find out about PCB fab
PCB Fab Express in California. http://www.pcbfabexpress.com 1-408-522-1500 Can they do 4 X 18? - Yes but custom. Max size they do is 16 x 22 Sent email requesting quote for our 5.8 GHz antenna. Attached 5.8cpa.pdf file
13-Jun-2011 0930 PDT Have not seen quote yet. Call them. Pretty clumbsy customer service, however the quote was a rough number $1500 to $2000 for the first board.
- Looked up the quote Glenn got from Sunstone back in 10-Aug-2010
First board was $1194.00 + $180.00 non-Recurring tooling charge. Two boards $720.00 each; Three boards $450.00 each. The quote provided Silver plating. Without silver was $50.00 less. Contact: Linda Postlethwaite
- Look up UHMW
On our wiki http://psas.pdx.edu/UhmwPeTape/ Called Jenifer at Multicraft Plastics 503-288-5131
8 inch width, 50 foot roll 0.062 inch thick UHMW PE 0.005 inch acrylic with mylar film adhesive.
Product is still available, special order. Adhesive on one side is available; she's not sure if adhesive on both sides is available but will find out. She will call me back on Monday with price.
13-Jun-2011 0930 PDT Jenifer called back. Double side is available but a bad product. One side wants to delaminate; a heat process is used to apply, and one side gets messed up during the application. They don't want to quote since it is a bad product.
Single side is available. 8 inch x 50 ft. $205.00 + freight from Ohio. In stock, takes 4 days to ship out.
- Andrew working on Python program to compute CPA