Search found 169 matches

by grant fair
Sat Jan 10, 2009 9:45 am
Forum: General Discussion
Topic: X-10 antenna question
Replies: 2
Views: 2131

The transceiver worked fine when the antenna was in one piece, but not when the antenna broke, until I held the two antenna pieces together with a short steel tube. It worked for a week or so then. When this arrangement stopped working mechanically (the tube no longer worked to hold the pieces toget...
by grant fair
Fri Jan 09, 2009 1:23 pm
Forum: General Discussion
Topic: X-10 antenna question
Replies: 2
Views: 2131

X-10 antenna question

I recently got some X-10 devices, including a transceiver which receives RF from a handheld RF-remote. Everything was working fine. Then I accidentally broke the antenna (an extendable 12" whip type) but held the two pieces together with a short piece of steel tubing. It was still working fine....
by grant fair
Mon Jan 05, 2009 7:34 pm
Forum: Projects & Kits
Topic: Reprogram Billy Bass
Replies: 4
Views: 15490

More on modding Billy Bass

Circuit Cellar Ink had a detailed article about 6 years ago - look through one of their indexes on the web.
by grant fair
Sun Jan 04, 2009 5:19 pm
Forum: General Discussion
Topic: replacing mosfets in dc motor controller
Replies: 2
Views: 2140

I replaced two mosfets. It works fine, maybe better than ever (it sounds better). So far, no detectable heat on these.

Thanks for your reply.
by grant fair
Sat Jan 03, 2009 5:32 am
Forum: General Discussion
Topic: replacing mosfets in dc motor controller
Replies: 2
Views: 2140

replacing mosfets in dc motor controller

I would lke to replace the 3 mosfets in an dc motor control for a mini-mill. (One of the mosfets is fried). I was using IRF840 mosfets (Rds of about .8, current capacity of 8 amps). The recommended replacement is the IRFP460 (Rds about .2, current capacity 20 amps). The three mosfets are paralleled ...
by grant fair
Mon Jan 01, 2007 8:21 pm
Forum: General Discussion
Topic: coloidial silver ??
Replies: 14
Views: 8302

I took a quick look at PubMed, a free searchable medical database. Searching on "colloidal silver" it showed 585 references. Many are not about health effects, but other uses or aspects of the stuff. Here's an abstract of a relevant article. Anyone really wanting a copy can request one fro...
by grant fair
Wed Dec 27, 2006 1:33 am
Forum: General Discussion
Topic: Lithium ion battery pinout mystery
Replies: 11
Views: 6154

I tried to zap various terminals, but never was able to deliver more than about 1/2 ma. I was using a current-limiting power supply set to 4.1 volts with the current limiting close to maximum. Today I backed off on the current limiting and zapped another pair of terminals for a while. I wasn't monit...
by grant fair
Tue Dec 19, 2006 12:32 pm
Forum: General Discussion
Topic: Lithium ion battery pinout mystery
Replies: 11
Views: 6154

Uh, another question:

According to information here:

http://www.batteryuniversity.com/partone-12.htm

it is unsafe to recharge a Li-Ion battery which has been below 1.5V percall for more than 2 days. Anyone have experience to the contrary?

Grant
by grant fair
Tue Dec 19, 2006 12:03 pm
Forum: General Discussion
Topic: Lithium ion battery pinout mystery
Replies: 11
Views: 6154

Thanks, Chris.

How does the sense terminal work? On a fully charged 3.7 v li-ion battery what voltage would it be?

Grant
by grant fair
Mon Dec 18, 2006 11:33 pm
Forum: General Discussion
Topic: Lithium ion battery pinout mystery
Replies: 11
Views: 6154

Lithium ion battery pinout mystery

My granddaughter bought a Geni G910, a Korean cell phone, without a charger. I've looked on the net without success to find a charger for sale. I then decided to build this simple one call charger: http://www.uoguelph.ca/~antoon/circ/lithium.html But - when I examined the battery with a voltmeter th...
by grant fair
Tue Jul 04, 2006 8:51 pm
Forum: General Discussion
Topic: What hardware does a HP 75000 Series C need?
Replies: 5
Views: 4105

PS- the Thaler website and data on the reference chip is at:

http://www.thaler.com/thchtml/mil_selector_refs.html

Grant
by grant fair
Tue Jul 04, 2006 8:47 pm
Forum: General Discussion
Topic: What hardware does a HP 75000 Series C need?
Replies: 5
Views: 4105

Hi Robert - I will be making a 10 volt voltage reference with a Thaler VRE 100. The HP 1.5 digit meter was initially selling for under $50. on Ebay; I think it is now over $500 - I lost interest when the price passed $50.00 I plan to do some metrology, so comparing various standards would be of inte...
by grant fair
Fri Jun 30, 2006 7:09 am
Forum: General Discussion
Topic: What hardware does a HP 75000 Series C need?
Replies: 5
Views: 4105

Many thanks. I looked at the Racal website for information and the related picture there made me think it was something like what you have described.

Grant
by grant fair
Thu Jun 29, 2006 8:28 pm
Forum: General Discussion
Topic: What hardware does a HP 75000 Series C need?
Replies: 5
Views: 4105

What hardware does a HP 75000 Series C need?

I am wondering about buying a HP 75000 Series C - E1410A - 6 1/2-Digit Multimeter. The seller says it needs a computer in order to operate. He was unsure whether an ordinary PC was needed, or a dedicated HP computer.

Does anyone know for sure?

Grant
by grant fair
Wed Jun 14, 2006 7:13 pm
Forum: General Discussion
Topic: What kind of wire is this?
Replies: 5
Views: 3017

Hi rshayes - Since I don't have an ohmmeter over 4.5 digits, the bridge will likely be the way to go. Thanks for answering some concerns/questions which have arisen. The inventor specifies an Omega RTD with a resistance of 1000 ohms (at the usual temp for specifying RTD's). He suggests a maximum cur...