Search found 140 matches

by Rodney
Wed Jan 11, 2012 5:29 am
Forum: General Discussion
Topic: lithium v/s nickle pros and cons....
Replies: 8
Views: 1984

Re: lithium v/s nickle pros and cons....

The biggest disadvantage of LiPo's is the fact that they are easily and almost always ruined if they become deeply discharged. You want to make sure that they never get discharged below about 3 volts/cell else they become garbage. I do not know if the tool makers have the units designed to prevent t...
by Rodney
Wed Jan 11, 2012 5:17 am
Forum: General Discussion
Topic: Intermittant TV remote controller
Replies: 11
Views: 2090

Re: Intermittant TV remote controller

Thanks to all who have replied. Since this is an old set and, since my first post, the buttons on the set itself started acting up (not responding properly if at all) I have just replaced the set with a new one. I had checked the battery connections on the old control module and they were fine (no a...
by Rodney
Sat Jan 07, 2012 7:20 am
Forum: General Discussion
Topic: Ni Cad battery packs to Ni-MH
Replies: 7
Views: 1619

Re: Ni Cad battery packs to Ni-MH

NiMh and NiCad are very similar in how they can be charged. The same charger can be used on either one; just, if peak detecting chargers are used, set the trip point for NiMh at about 5 millivolts while the NiCad can use about 10 millivolts. Now, if slow charging (being defined as charging at 0.1C) ...
by Rodney
Wed Jan 04, 2012 11:36 am
Forum: General Discussion
Topic: Intermittant TV remote controller
Replies: 11
Views: 2090

Intermittant TV remote controller

I have an older (1992 vintage) TV that is still in good working order and used regularly. However, the controller is becoming very intermittent. Sometimes, when a button is depressed, nothing happens; i.e. it takes several presses on a button to have any effect. The batteries are not the problem, re...
by Rodney
Wed Dec 28, 2011 7:56 am
Forum: General Discussion
Topic: Florescent light problems
Replies: 6
Views: 1575

Florescent light problems

What is the most common (and any suggested solutions) to why florescent lights do not turn on. I often have to switch the switch on/off several times before the lights go on. There are sometimes brief flashes as the switch is activated but the lights do not stay on. This seems to be worse as the wea...
by Rodney
Mon Sep 05, 2011 12:39 pm
Forum: General Discussion
Topic: A Little Transistor History?
Replies: 15
Views: 2833

Re: A Little Transistor History?

Oh, what the heck .... I can help keep an old OP going. Anyone remember the Raytheon CK722? It was one of the most popular hobbyist transistors of the 1960s. You could get a bag of 10 of the things for a buck from Poly-Paks. 'Course, the Poly-Pak transistors didn't always work as advertised...... I...
by Rodney
Sat Jun 04, 2011 1:39 pm
Forum: General Discussion
Topic: Field strength meter for 2.4GHz low powered transmitters
Replies: 4
Views: 1256

Field strength meter for 2.4GHz low powered transmitters

I need to be able to determine if my 2.4GHz radio control transmitter is putting out an RF signal. No need to detect the modulation pattern, just is there rf out or not. The simple circuits I used for the 72MHz stuff doesn't seem to work, probably because my junk box does not hold any diodes capable...
by Rodney
Tue Nov 02, 2010 8:14 am
Forum: General Discussion
Topic: Battery Testing Plan
Replies: 3
Views: 933

Re: Battery Testing Plan

In working primarily with NiCad but also NiMh, I have found there is no foolproof and FAST way to check out old batteries. The only reliable way I have found is to charge them at about 0.1C (that is at 1 tenth their capacity) for 15 to 16 hours. This insures that all cells are fully charged yet the ...
by Rodney
Tue Oct 26, 2010 2:02 pm
Forum: Computer Programming
Topic: Borland C++
Replies: 2
Views: 1200

Borland C++

I have an old version of Borland's C++ (10 3.5 inch disks) but they will not load on Window XP. Do you know of any way to re install these disks or should I just junk them and look for a new C program? I have dropped out of the programming habit a few years back but am now interested in getting back...
by Rodney
Sat Oct 23, 2010 9:20 am
Forum: Computer Programming
Topic: USB to serial dongle for Linux
Replies: 2
Views: 1198

Re: USB to serial dongle for Linux

That is one of the many nice things about Ubuntu, most devices are already covered with no need to search for drivers etc.
by Rodney
Fri Sep 17, 2010 2:08 pm
Forum: General Discussion
Topic: DIP KS20968L1, what is it?
Replies: 1
Views: 549

DIP KS20968L1, what is it?

I have two 14 pin DIP chips made by NS with the part number KS20968L1 marked on them. I can not seem to find any info on them when I search the web. Can anyone tell me what they are and what the pin out is? Thanks.
by Rodney
Thu Sep 16, 2010 12:11 pm
Forum: General Discussion
Topic: Can anyone define a 14 pin DIP NS 20968L1?
Replies: 3
Views: 881

Can anyone define a 14 pin DIP NS 20968L1?

I have two integrated 16 pin chips I am trying to identify as to function (data sheet hopefully) but can not find any reference to them by Googling or other searches. They must be a special order or very obsolete. Any info will be appreciated. They are stamped NS 20968L1 and seem to be a standard 14...
by Rodney
Fri Sep 10, 2010 9:55 am
Forum: General Discussion
Topic: Voltage Rating of Capacitors in Series
Replies: 7
Views: 1326

Re: Voltage Rating of Capacitors in Series

In general, this is not a good idea, especially if using polarized capacitors. Not only must the two capacitors be quite closely matched any heating caused by ripple currents can upset the balance. In some cases, paralleling each capacitor with a large value resistance will help with the voltage bal...
by Rodney
Sun Aug 29, 2010 7:20 am
Forum: Computer Programming
Topic: Form factor for memory cards?
Replies: 0
Views: 1135

Form factor for memory cards?

Is there a source for the physical shapes, sizes, key positions etc. for the various memory cards that plug into the typical desk top computer mother boards. A drawing showing the typical differences would be helpful.
by Rodney
Sun May 30, 2010 1:30 pm
Forum: General Discussion
Topic: Soldering irons, stations, Ungar still in business
Replies: 12
Views: 3098

Re: Soldering irons, stations, Ungar still in business

I've used the Weller TCP series stations for 25 years. The tips have a thermomagnetic slug in the end that sets the temperature by cycling a magnetic switch in the handle. Several heat values and a wide range of tip sizes are available. In all the years I've repaired the irons several times and it ...