- Thermo-Electric Cooler (Peltier Junction Device)
- DC Power Supplies
- Temperature Probes
- Digital Multi-Meter (DMM)
You will always need a lab notebook (with page numbers and
non-tearable pages), a good felt pen (to write on the back of
polaroids) and lots of polaroid film.
Useful shops:
(Note: Always check the latest phone directory for more info. In the
following Steve implies Steve Nicholas. Steve Carlough is simply
referred to as "Carlough" or "the new guy". Also, I have started
collecting a lot of catalogs in the farm. Check the shelf behind
the farm door.)
1. Sager Spuck Supply Co. (Albany) 436-4711
- Good industrial supply store. They had tungsten carbide
drill bits (good for hard metals, ceramics) [not compatible
with the DREMEL tool (with Steve) though].
2. DREMEL - 800-437-3635
- Ordered a set of tungsten carbide drill bits (1/8" shank) to
drill a hole into the Thermo-Electric Cooler (TEC) (cost about
$40 for next day delivery for a set of two). Steve has a
DREMEL tool available. NEWARK catalog offers DREMEL tools
etc.
-(Feb 10, 95) Ordered two 9909 tungsten carbide bits (the shank
is 1/8" and it tapers to a point) from DREMEL for TEC.
They filed it under CIE,RPI.
-(Feb 21, 95) Drill bits seem to be very tough. Though due
to not having a drill press to hold the DREMEL tool we could
not drill the hole into the TEC ceramic plate. We will try
the central machine shop.
3. DC Power Supplies
- You will find tons of pages on DC-power supplies in the
EEM (Electronics Engineer Master Index) catalog with Steve.
Though you might not be able to find anything
useful. We were looking for a good dual output (at
least) DC power supply for the 9th floor test lab.
This would have removed the necessity of borrowing
power supplies from Steve. Also, we wanted higher
wattage power supplies so that they can supply,
e.g., 10-15 Amperes at 6 vdc. Here are a few of the
companies we talked to finally
- Instek (Page 1754 in EEM-D catalog) in California.
They have heard about RPI and give 5% educational
discount. They sell single/triple output power
supplies and one interesting one was a single output
18V-10A power supply. The price for a power
supply+LED display was $412+$75 (LED Display)[before
discount]. Instek also sells a triple output power
supply with two variable outputs (30V-3A) and one fixed output
(5V). The two variable outputs can be used in
serial/parallel configuration. So we can get 60V-3A
or 30V-6A from the same supply. But we need more
than 6 A.
- HWD (Page 1838 in EEM-D catalog) sells a 10V-15A
single output supply for $950.
- Steve has a couple of power supplies (rack based) in
CHD lab which can go to astounding values of Current/Voltage.
Supposedly, one of the power supply with LED output can
supply 0-7.5 V with upto 200 A (1800 W !!!). This should
be sufficient for the MCM where we need about 200 W. Therefore
for right now we will direct our energy to a smaller power
supply such as 18V/5A or 18V/10A.
4. Temperature Probes
- Temperature measurement is needed to for our tests
due to a high power dissipation. We found an
infrared thermal probe compatible with Steve's
digital multimeter (DMM) by Fluke for about
$200-230. It has a 4:1 optical ratio which implies
that if the area of interest has a 1" diameter you
can not keep the probe farther then 4 inches. The
minimum it can measure is 1/8" (in this case you have
to put the probe nozzle (dia - 1/8 ") right next to
the spot.
- Hans talked to somebody at Tektronix who has ordered a
IR probe (not from FLUKE). Once they get it we will know
how it performs. Though, their requirements are not as
stringent as ours.
5. Digital Multimeters (DMMs)
- Hans has put his DMM in the 9th floor lab. We
needed one more DMM so we tried Fluke's 79 series
($210 approx.) and also at Type 83 and Type 79. One
problem with 79 series is that its current range
goes only upto 10 A. I will have to check with Fluke
if they have something larger than that.
-(Jun 95 - Atul) I am using these DMMs to measure
the voltage across the on-wafer resistors and the
current through the whole resistor structure. Due to the
need for measuring a variety of resitors (metal, NICR,
ceramic etc.) I need very good accuracy from
microamperes to a few milliamperes. What I have found is
that these DMMs are not very accurate and you have to be
careful in interpreting your results. For example, if
your meter is set for 2 mA max (DC) and you read 0.190
mA (i.e. 190 microamps), changing the range to 200
microamps on the meter couild change the reading to
195 microamps. So whenever you are in such regimes make
sure you double check the readings.
6. PENSTOCK(catalog)
- They stock SMA connectors/cables etc. We were
looking for 12-dB attenuators.
7. Polaroid Films / Screen Grabs
- Finally, I found the Polaroid 667 professional at
the "Film to Frame" shop in downtown Troy. Previously
they were called Berns Camera and Video.
- Nowadays people have started using electronic capture
methods to grab the scope output. It seems for less tahn a
thousand dollars you can have a CCD camera with enough
resolution which can take a good picture of the scope which
you can download directly into your PC/Mac.
8. Microwave components suppliers
-HP, Tektronix, W.L.Gore (very expensive)
- Powell electronics, Sealectro, Mid-West Microwave
Test Equipment Available at RPI high-speed lab
Tek 11801A (Dr Gene Rymaszewski)
1. Depending on sampling head it can support fast rise time and wide
bandwidth.
2. Sweep speed range: 1ps -5ms per div (adjustments in 1ps/div step)
3. 200 KHz sampling rate for high system throughput and real time
display.
4. Full function dc coupled pulse trigger to 2.0 GHz.
5. Single-ended and differential TDR measurements on all channels (upto 8
possible) using
SD-24 sampling head.
An analog scope displays a trace dynamically as a beam is swept acrosss
the display
horizontally. A digital scope separates a trace into discrete digital
samples. It captures a
trace before any amplification or attenuation is used to manipulate the
signal. This
technique provides very high bandwidth for repetitive signals and makes
bandwidth a
function solely of the sampling head. Thus the capability of a digital
sampling scope can be
increased just by adding a higher bandwidth sampling head.
SD-24 sampling head
1. 2 channels with signal acquisition and step generator capabilities. In
addition to signal
sampling, the two channels let you perform differential and common mode
TDR and TDT
measurements.
2. Both step generators have switchable polarity with 250 mV ramp.
3. Typical displayed TDR incident rise time - 28 ps
Acquistion rise time <= 17.5 ps
Reflected rise time <= 35 ps
B/W = 20 GHz
From hgreub Fri Mar 10 12:45:24 1995
To: mcdonald
Cc: garg
Subject: GGB
Date: Fri, 10 Mar 95 12:45:21 -0500
From: hgreub
X-Mts: smtp
Status: RO
Jack:
We got the GGB probes in.
We have now two 40 GHz GSG probes and a six channel probe with two power
connections. The GGB S-Parameter measurement show at least a bandwidth
of 10 GHz on the probe on the worst location (for the ground connection).
Hans