I have at work a very old Tek model P6042, it is an active probe DC to 50MHz.
I made my company buy it from eBay 13 years ago. I worked with it before, when I just started: it is an 80s - built model.
It was designed by Tek in 1967.
Indispensable.
I plan to buy one on eBay when one in working condition comes cheap.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
dconant Wrote: I don't have such a tool and really don't know what it is
You may have seen clamp-on ammeters which can measure the 60 Hz line current used by an electronic or electrical piece of equipment. The Tektronix P6022 does something similar when connected to an oscilloscope, but at higher frequencies (up to 100 MHz) and lower currents.
The seller was selling one, the 6042 for $299.
I offered $100, he countered $150.
I accepted.
Always wanted one.
But the one I made my company buy was about $800.
Let's see what condition it is in. The note says "Seller Notes
“Excellent condition. Fully functional.”"
I don't expect it to be shiny and so on so forth, but if it is not functional, well, 1) I can hold the seller to it, 2) I can repair it.
But let's hope that, other than possible potentiometer issues (very common, this is what Deoxit and replacements are for) there other no others.
The original one I worked for 35 years ago with, developed broken wire inside the probe cable. Exactly where the boot entered the case. I fixed that one.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
morzh Wrote: But let's hope that, other than possible potentiometer issues (very common, this is what Deoxit and replacements are for) there other no others.
I am about to use my DeoxIT FaderLube on a noisy potentiometer. It is the volume control in my Sony SRF-M70 Sports Walkman, which has been my AM/FM analog reference receiver for work for about 35 years.
I managed to find a few minutes to poke around with the 60. I am 100 percent sure the band switch is working as it should. I mentioned earlier doing some resistance reading on the band switch between two different 60s finding a 2 meg difference. That turned out to be the volume control. On the nice playing radio the pot is 350K and the other radio is 2 meg. The schematics all say 350K for the pot. I doubt that is causing the problem I am having or is it?
This set is a rather straight forward radio, very similar to AA5 sets only with a power transformer. I don't think that the volume control has anything to do with your problem.
Check the antenna coil. From the ANT to GND terminals, the reading should be about 11.7 Ohm in broadcast mode and 0.7 Ohm in SW mode. It is not uncommon to find this coil open because of lightning hits. Also, make sure that the switch that shorts out the BC Band primary on the antenna coil works. This is part of band switch #2 on the following schematic: https://philcoradio.com/library/download...l.%201.pdf
Seems to me that the BC coil is 11 Ohm and the SW coil is 0.7 Ohm. Check the secondary of the antenna coil and the secondary of the oscillator coil (the secondary is the one that is tapped. the band switch shorts certain primary and secondary windings of the antenna coil and shorts the middle of the oscillator coil secondary in 3 separate circuits. Make sure that this switch works.
Hope this helps.
"Do Justly, love Mercy and walk humbly with your God"- Micah 6:8
"Let us begin to do good"- St. Francis
Hello MrFixr55, I have made the checks you pointed out. Also checked all four switches on the band switch. I either get the correct resistance reading from the coils or a short except switch connected to #11, it is either a short or open. On the schematic which I included would you please explain why #11 is showing 1400 PF. My radio has the 1400 PF cap instead of the compensator. I assume in a later run they removed the compensator and used a 1400 PF cap instead. The schematic came from the Evolution of the Philco 60. I would include that link but I can't find it anymore on the Phorum.
Is Compensating cap # 12 in your radio? I am not completely sure of the purpose of either 12 or 11 as adding capacity would lower the resonant frequency, and in SW Mode, 11 and 12 are essentially parallel. However, when the center section of the oscillator is shorted out, that would raise the resonant frequency as expected. The way that the schematic is drawn, we have to assume that all switches are open in Broadcast Band and closed in Shortwave (Police) band. We certainly can't call Philco Tech support or ask the designing engineer as both are deceased (pausing and saying the Requiem Aeternum for the designer), but you may want to ohm the switch to determine if shorted or open in SW. Has the cap been changed? Do you receive stations at the correct dial settings? If the Police band starts at 1.5 MHz you should receive several AM stations from 1600KHz to 1700KHz in the "Police" band.
"Do Justly, love Mercy and walk humbly with your God"- Micah 6:8
"Let us begin to do good"- St. Francis
Yes #12 is in my radio and I did change the 1400 PF cap. I do receive most stations where they should be. I get 740 and 1180 spot on but 800 comes in about 820. Station 800 has more noise than 740 although both in Toronto. Alignment instructions say #11 is low frequency for police band and #12 is low frequency for AM. I do receive AM stations between 1.5 mhz and 1700 on the police band but above that I get an single unknown AM station from there to the end of the dial. I have notice pins 3 & 4 of the 75 tube go the secondary of the 2nd IF and on to the volume control to ground. Would this effect sensitivity of the radio? The volume control is 2 meg where it should be 350K. All 4 switches are open in the broadcast band and shorted in the police band.
Well after many hours verifying my wiring, parts and that band switch I am happy to say the problem is resolved. I found nothing wrong so I decided to do another alignment. It was way off. I wounder if I did the initial alignment when I was on the police band. I now receive SW stations and the higher AM frequencies at the low end of the band. I just wouldn't let it lick me.