new mistress is an older gal

[ARSKF9NY]

If your ever in the St. Louis area let me know...I have a scope (Tektronix TH-710). Curious, I read about the passive devices in your descriptiion. Did you upgrade any of the active compnenets also?

[bigbillinsc]

if you mean solid state devices... NO! i replace the capacitors because of the age and so many yyears sittin in a garage/shed/closet/wharehouse/who knowswhere.... capacitors are active devices. and since i was in there in any how i decided to go ahead and replace the 5 and 10% resistors with tighter tolerances. and its rare, very rare for solid state devices to go bad just by sitting. they break down with usgae. no current flow nothing to harm them. it seems to work pretty good and i am very pleased with it. one drawback....


its like swinging a brick all day compared to the prizm 3.


happy huntin yall

[joecoin]

Bill,
Since you didn't replace any of the pots, I assume you cleaned them. What did you use? Also, did you measure their impedances to be certain they were still in tolerance?

BTW, we still repair TV's here in Ohio, they just have to be PITA big screens.

Joe

[ARSKF9NY]

Originally Posted by bigbillinsc

if you mean solid state devices... NO! i replace the capacitors because of the age and so many yyears sittin in a garage/shed/closet/wharehouse/who knowswhere.... capacitors are active devices. and since i was in there in any how i decided to go ahead and replace the 5 and 10% resistors with tighter tolerances. and its rare, very rare for solid state devices to go bad just by sitting. they break down with usgae. no current flow nothing to harm them. it seems to work pretty good and i am very pleased with it. one drawback....


its like swinging a brick all day compared to the prizm 3.


happy huntin yall

Yes, I was referring to active devices as solid state devices, which are defiend as Transistors, IC's, etc... in engineering terms I am pretty sure resistors, caps, and inductors fall into the category of passive devices, since they do not provide response to input such as current gain (transistors) or voltage response (tubes).

In regard to solid state devices going bad I agree that they do not have nearly the same depreciation of performance over time as espcially a cap or resistor, my thought was with some research, there might be commercial/military grade equivalent devices which if in no other event will provide a larger temperature range of operating stability. And there is a good chance there will be other devices which have much less inherent noise factor. Doing so problably will not result in any earth shaking addition to overall performance to the unit, but it might give what I endearingly call a "performance animal" the satisfaction of knowing they have that unit as tight as they can get it.

Anyway glad to have another geek to talk about this stuff with. I really enjoyed reading about your new "mistress".

[bigbillinsc]

i didnt think this wold turn into a tech thread. not my intentions at all.

To clean the pots and switches i used TUNER RENEW from chemtronics. yes i measured the pots out of crcuit. my GEB has a dead spot on it at the very top end. i dont think i will ever be detecting in an iron ore mine so that isnt much of a problem for me.


i dint replace any solid state devices because as previous mention i didnt think any where bad, and second because i didnt want to have to go through and figure out if everything was biased properly. with all the new transistors having such higher gains and sensitivies it could end up a night mare trying to go through this machine with just a digital meter trying to set bias.

i didnt want to RE-engineer the machine.... just give it a few more years of life.

[Mr.Silver]

Did you ever think of makin a hipmount out of your machine I did I had to w/ the weight of the batterys(nicad consists of 18 AA) I use use a camera strap with old D-rings white's used to sell, they go right on the detector, use extension cable,
and a support to hold your detector made of aluimuin the same shape of the detector. Its really simple.

Mr.Silver