However: Putting a 100M resistor in series with a 10K resistor forms a 10000-to-1 voltage divider, not a 1000-to-1 voltage divider as the original poster indicated. Mike Dinolfo N4MWP

Rocky: Harvey White's recommendations are good, and you definitely should verify that power supply voltages are what they should be, and that ripple on the DC supplies is not excessive. I recommend th

I have a "plain" 465 (non-A, non-M). I just checked (the 465 has been sitting unused in a conditioned space at about 68 degrees F for several weeks), and the fan runs continuously as soon as the unit

to nanovnauser@...: The Tek P6430 manual can be found at: https://w140.com/tekwiki/wiki/P6430 but I don't think it includes a schematic of the P6430 probe. I think that the P6430 probe is basica

The method suggested by John Kolb is somewhat similar to a method described at https://www.londonsound.org/Vintage%20valve%20hi-fi.htm And although the "London Sound" method was apparently intended to

James: I'm glad that my suggestion helped you somewhat with your 455. Your issues with the vertical deflection could be just about anything, but start by doing a visual check (and maybe a "wiggle chec

James: A comment about the 455 with the low +95v rail that you described: Check the following components: C582: 2.2 ufd cap, electrolytic, 2.2 ufd +50/-10%, 160V C584: 2.0 ufd cap, electrolytic, 2.0 u

The first thing you should ask your friend is what the serial number is for his 453. w140.com has the operator and service manuals- there's one set of manuals for serial numbers up to 20000, and anoth

W2AEW has an excellent 19 minute video on youtube where he uses a variable bench power supply and an oscilloscope (Tek, of course) to demonstrate and measure characteristics of a tunnel diode; it's pr

I believe that some of the 465 models (generally, the ones without digital display/measurement units such as the dm43 or dm44) were "mostly" manufactured with a 10-turn graduated (metal knob) delay ti

Ken: OK- from your response, it's clear that you have correctly evaluated the condition of the resistor. Too bad it's defective, and I can only wish you luck in tracking down a replacement. And happy

Ken: How did you determine that the "old" resistor is bad? Did you measure its value? If you handled it during the measurement process, I recommend that you handle it only while wearing nitrile gloves

Toby: I don't have a 606, and I'm not very well versed in circuit design, but it appears to me that the polarity of CR591 (in the schematic that you provided a link to) appears to be incorrect. I thin

Ananda: An Ebay search (in the US) for "tektronix cover" comes up with several options, including model # 200-2520-00, which should fit. I don't know where you are located, but the seller ships to man

I have a Arium ML4100 Logic Analyzer, and a working Tektronix R7603 oscilloscope (with assorted plugins), and several other Tek "parts donors" items, that I wish to dispose of. I am offering these ite

Jeff: Have you considered doing your receiver/receptor output measurements with an analog meter, such as a vacuum tube voltmeter (VTVM) or perhaps an analog FET voltmeter? These devices typically have

As Jean-Paul wrote- verify that the battery contacts (and batteries) are OK. I had similar issues on my 260 (series 2); I found that a can of compressed air applied to the zero pot and the range switc

I believe a bare #18 AWG solid (not stranded) copper wire conductor (or the male pin from a DB-9 or DB-25 connector?), are a nice makeshift fit for the 0.040 female "calibrator" connector on a 76xx sc

Dominic: How about the following as a possible source: http://electrontubestore.com/index.php?main_page=product_info&products_id=2480 (10) diodes for under US$12.00. Claimed to be equivalent to Tek 15

Don't know if they have shock mounts that will work for you, but I recently came across shock mount-type items at mcmaster.com. Try https://www.mcmaster.com/bumper-cushions/ I'm not the first to sugge