Buying the basic Lab eqipment

                                 Choosing a starting area
I'm going to start with Audio because I can simply breadboard the circuits and check them out instead of having to solder them. Audio frequencies are under 20KHz, easily the range of operation of any breadboard. Also, the oscilloscope hardly needs to be be high performance as do the function generators and probes. Being a conservative fellow, I always like to start slowly, inexpensively with simply projects and add complexity to them


                                       The equipment
We need the following equipment to get started
1. Oscilloscope and probes: Up to 1MHz BW
2. Function Generator and associated BNC connectors: Up to 1MHz
3. DC power source and associated power clips: Decent PSRR up to 20 KHz

This is hardly the equipment you can pick up at the local walmart. Let's start off with Ebay. Best place for exotic items like this


                                         The Sellers
1. Ebay : online. Surprisingly this is not the cheapest way to get what you want, if what you want is a generic item. Ebay is great for items that are hard to find. I found a DC Dual power supply to be a lot cheaper when sourced from a shop selling test equipment than from ebay. Also, the shipping on ebay products is prohibitely high as well. Up to 3 times more than from a commercial seller. Either the commercial seller has some deal with the shipper due to the volume or else shipping costs are a big part of revenue for the individual sellers on ebay. Not sure.

2. Alibaba: online. Some very cheap Chinese equipment. But not sure about quality.

3. http://www.ladyada.net/library/procure/hobbyist.html

4.Some local electronic test equipment sellers

5.  https://www.valuetronics.com/ : looks like a great site if legit
           a. tek 2213 for $229. others for up to $90: https://www.valuetronics.com/detail/Used-tektronix-2213.cfm#.UaD2bs-fEuo
           b. kenwood Pw-18 power supply for $65: https://www.valuetronics.com/detail/Used-kenwood-pw18-2.cfm#.UaD1qc-fEuo. This stuff is going for $250-500 on ebay, Yikes!
           c.   Function Generators are a little more expensive than in ebay. Here is a tek one for $125. https://www.valuetronics.com/detail/Used-tektronix-fg501.cfm#.UaD3Ms-fEuo:


                                       The Economics
1. First hand agilent sells a function generator for $2000, Yikes! That's too much for something under 1 MHz. Funny that function generators are harder to come by than oscilloscopes on ebay. You would think these are easier to build than scopes.
2. A shitty brand new hand held oscilloscope goes for over $300.
3. DC power supplies from China seem to come in around $50 on ebay. What do they cost in china itself?
4. Damn, passive probes are expensive. Brand new 100 MHz is over $65. At ebay, it is $14. 100Hz is really the cost effective BW for a probe. Till that point, the prices do not increase a whole lot with BW. But after that the price just shoots up.  Considering that a 400 MHz probe costs $40 on ebay, perhaps a 300 Mhz oscilloscope used fair price is probably around $250?

                      

                                     Final Buying Price
The First 5 items are from ebay
1. Tek 2465 4 Channel 300MHz Oscilloscope: $270 + $42 (ship) = $312
2. Function Generator GW-Instek: $72 + $15(ship) = $87
3. 100 MHz OScilloscope probes: $14/pair
4. BNC cables: $10/pair
5. Banana to alligator clips: $3/pair

Did not get any great deals from ebay for sure, but did not get ripped either.The next item is from valuetronics

6. Kenwood PW18-2 Dual DC power supply: $65

Ebay bidding tips

If you are going to be setting up an electronics laboratory on a reasonable budget, you will be looking to ebay a lot to find used test equipment. Some tips are in order. These are not the best, but basic

1. First start looking outside of ebay to see what these items cost outside of ebay, via established businesses. Typically I would be willing to spend 75% that amount on ebay.

2. On ebay itself, Start of with looking at items that have already been sold which are similar to the items you are looking to buy. That will give you a ballpark idea of how much you may need to spend. This amount is usually 65% of what you could expect to buy for from an established businesses

3. Start bidding on items that are going to expire soon, i.e. within 2-3 hours. No point bidding on items that have two or more days to go. The bidding process seems to get very hectic near the very end, within the last few hours. Sniping might even happen at the last minute.

4. Take a look at similar items (to the ones you are bidding on right now), but which will expire a little later (than the item you are currently bidding on). You should be willing to pay about 10% more on the current item. For some specialty items, this may be hard.

5. Just make sure you do not place a maximum bid that is higher than 1. or 2.

Ebay should probably add a new algorithm to prevent sniping. Every time someone makes a new high bid, there should be an automatic time extension of 5-10 minutes to give the other bidders time to respond.  Basically, there must be at least 5-10 minutes for the new guy to respond with  higher price. This is better for everyone except the sniper.