Eric Foster
New member
Some Goldscan 5's will be heading out to Mr Bill, early next week. It has taken a little longer than anticipated, as is usually the case when something first goes into production testing. Still, from my point of view it was definitely not worth rushing units out as a couple of areas in the electronics have now had some extra attention.
One was with an on board switching charge pump power supply, these always generate a small amount of noise, and because of the higher gains in parts of the ground balance circuit, this needed to be addressed. Result - the noise has completely gone and the charge pump driven by picking off part of the transmitter drive.
A dc level adjust circuit in the receiver was much too critical and would easily go out of adjustment. The user would not have noticed this, except maybe for a small change in threshold setting over a period of time. A couple of extra components cleared this up, resulting in a more stable setting.
Last but, not least, I got a duff batch of the polyurethane jacketed coax that I use for the coil cable. The outer jacket is supposed to be 0.8mm thick, but on this lot. it thinned to 0.2mm on one side. This would have made the cable more vulnerable to cuts and abrasion. If used on the beach and sea water got in, the whole coil could be a write off. The good replacement cable is in, and coils can now be finished and potted.
We get very few returns for manufacturing and design problems and both myself and Mr Bill want to keep it that way. Better to spot and rectify even small problems now, than later when machines are out in the field.
By the way, no DIY attempts at tweaking are allowed and will certainly invalidate the warranty. I have a test sheet for each detector and all settings are recorded. You can be assured that the Goldscans are set up for the best performance, and also uniformity of performance between units. Any unauthorised adjustment will only degrade this.
Eric.
One was with an on board switching charge pump power supply, these always generate a small amount of noise, and because of the higher gains in parts of the ground balance circuit, this needed to be addressed. Result - the noise has completely gone and the charge pump driven by picking off part of the transmitter drive.
A dc level adjust circuit in the receiver was much too critical and would easily go out of adjustment. The user would not have noticed this, except maybe for a small change in threshold setting over a period of time. A couple of extra components cleared this up, resulting in a more stable setting.
Last but, not least, I got a duff batch of the polyurethane jacketed coax that I use for the coil cable. The outer jacket is supposed to be 0.8mm thick, but on this lot. it thinned to 0.2mm on one side. This would have made the cable more vulnerable to cuts and abrasion. If used on the beach and sea water got in, the whole coil could be a write off. The good replacement cable is in, and coils can now be finished and potted.
We get very few returns for manufacturing and design problems and both myself and Mr Bill want to keep it that way. Better to spot and rectify even small problems now, than later when machines are out in the field.
By the way, no DIY attempts at tweaking are allowed and will certainly invalidate the warranty. I have a test sheet for each detector and all settings are recorded. You can be assured that the Goldscans are set up for the best performance, and also uniformity of performance between units. Any unauthorised adjustment will only degrade this.
Eric.