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THE AM BULLETIN BOARD => QSO => Topic started by: WBear2GCR on March 20, 2017, 02:04:00 PM



Title: Panoramic SP3/25 "Panadapter display"
Post by: WBear2GCR on March 20, 2017, 02:04:00 PM
This is the second Panoramic SP3/25. The first is as Panoramic Radio Products unit, this one is a later mfg Singer-Metrics unit.
Appears to work, slightly "hard of hearing". Will get into the input amps after I find out why the #1 unit is stone cold deaf. This one seems about 10dB down in gain (guesstimate) based on the specs. Shown with the 500kc marker engaged and the IF output of a nearby R-392 receiving a moderate strength (1/2 signal strength scale) BC signal. That signal is the lower one to the left.

Thinking about it as I type - I think this means that the IF of the BC-392 is badly misaligned, since it is supposed to have a nominal 500kc IF (iirc). Of course if it is a 455kc, then it's about right. :D

White, long persistence phosphor trace.

Yes, I do know I can do the same bit with a USB dongle and a laptop, and not a two rack unit high unit,  but is it really the same thing? :D

 



Title: Re: Panoramic SP3/25 "Panadapter display"
Post by: KB2WIG on March 20, 2017, 02:38:21 PM


Peeps are used ta fancy stuff on the computor screen, but oscopes and rackmount equipment,  well, thats special.


KLC


Title: Re: Panoramic SP3/25 "Panadapter display"
Post by: w3jn on March 22, 2017, 07:35:50 PM
R-392 is a 455 KC IF.  R-388 and 51J-4 are 500KC IFs.


Title: Re: Panoramic SP3/25 "Panadapter display"
Post by: WBear2GCR on March 22, 2017, 10:04:39 PM
Yeah, thanks John!
I "knew that" - but...
...anyhow that display makes perfect sense. :D
Worked on the #1 unit today - turned out the switch on the first Atten position was toasty.
It's a KAY, teflon "Mega Switch" (says so on the face of the panel bushing!). The same switch
used in those precision RF attenuators that have a bunch of toggle switches. Just like those units
someone put too much power on the input and smoked a resistor. But the switch showed open, after
a bit more checking and pulling the switch.

So, I drilled the rivets and decided to have a look inside.
neat switch!

It's got a Teflon barrel with gold rings on each end that is permitted to roll from one end of the switch to the other on a gold plated track- then it bangs into the sides where there are some gold plated contacts that go through the wall (teflon).
On this switch the gold contacts were blasted where the contact was made.

So, since it is Teflon, I rotated the contacts in the body to find a clear gold surface and put the switch
back together with 2-56 hardware. Replaced the two dead 1% metal film resistors. 4 hours later... all good!

That's the short version.

Tomorrow we see if it "hears" now - it was stone cold deaf before! HA!

                  _-_-


Title: Re: Panoramic SP3/25 "Panadapter display"
Post by: W3RSW on March 23, 2017, 04:00:48 PM
Wg, no it's not the same thing as an SDR GUI, but the last time my Robot Slow scan got used was 22 years ago in a neighbor's haunted house display with a continuous running pumpkin pix. The guy put a major scratch on what was a pristine cabinet.

I so treasured that P7 phosphor, antiquated even back then that that was the only neato use I could think for it , sigh.

Guess I could hook up my old Sony recorder/player and look at my wa3ypi tapes again.
Can't even take it to a fester or club show and tell unless in a darkened room. display.

The stuff I've done with my qs1r even as early as 2008's been fantastic, including finding resonance, passband , etc. of LCR combos, filters et al using the little attached qs1e feeding thru the unknown and displayed on the 1r receiver.

Enjoy the rack stuff. Soon few will be able to use, let alone fathom, it.  ;D


Title: Re: Panoramic SP3/25 "Panadapter display"
Post by: Opcom on March 24, 2017, 07:38:44 PM
I'm glad it's working. Can't be a cool CRT display.


Title: Re: Panoramic SP3/25 "Panadapter display"
Post by: WBear2GCR on March 25, 2017, 09:02:50 PM
I'm glad it's working. Can't be a cool CRT display.


sure you meant "can't beat..."


Title: Re: Panoramic SP3/25 "Panadapter display"
Post by: Todd, KA1KAQ on March 27, 2017, 10:27:16 AM
Did you get the nifty table top cabinet with either of them?


Title: Re: Panoramic SP3/25 "Panadapter display"
Post by: WBear2GCR on March 27, 2017, 04:56:35 PM
Nope these are destined for rack mounting, along with a suitable receiver...
I usually don't "go for" racks, but I've made an exception for this stuff.
Still going to go with a frame rack, and homebrew heavy duty rack shelves, for ease of serviceability! :D


Title: Re: Panoramic SP3/25 "Panadapter display"
Post by: Opcom on March 27, 2017, 06:58:40 PM
I'm glad it's working. Can't be a cool CRT display.


sure you meant "can't beat..."

I am sure that yes I do mean that the CRT can't be beat. The CRT is the ultimate achievement in analog display evolution. This CRT must survive.

If you go for racks, my simple advice is make them as tall as possible. Saves floor space.

If you ever make it to Dallas, there is another equipment here, just like what you have. I probably will never use it and you are welcome to it. It is somewhat dirty but a supply of spares at the least would be of value.
AMfone - Dedicated to Amplitude Modulation on the Amateur Radio Bands