An inquiry to M3 about the SPO-10

[FoxAlfa]

I don't know mate :dunno:

 

Ok, what we have, two different pilot training manuals that say the same thing, your incomplete documentation (lacks impulse graphs that trigger diodes) that says there is more stuff going on then signal->blink.... what can we add more.... OK, how about the construction of the L-006LM antenna (four of them for each direction were on the aircraft) from the SPO-10 which it self has 4 arrays to handle different signal strengths levels with the 1.9оm, 5.6om, 5.8om and 28om resistance as far as I can tell from the manual.

 

You can clearly see them on this video:

 

I don't know but I feel that trumps your hunch mate. The main issue with translations is that SPO-10 has 4 antennas with 4 channels each, and it is easy to mix them up.

 

Again people tend to oversimplify the SPO-10 and what it can do and information it can provide.

Edited May 13, 2019 by FoxAlfa

[Bogey Jammer]

Dude, are we talking about the same system ?

This is what I'm talking about, the damn SPO-10 complete set installed in the MiG-21bis:

 

 

 

• The video you posted clearly deals with another system. I have no idea why the guy with his stupid irritating lazy accent said it was installed in a MiG-21. That device looks like too modern to me anyway.
  
• I also don't see any reference to your L-006LM antenna anywhere in the SPO-10 documentation. If you want to talk about antennas, the only references possible are S3M-7S for the antenna itself, and S3M-8M for the adapter, nothing else.
  
• Nowhere in the SPO-10 documentation it is mentioned that each of the 4 channels has 4 sub-channels with different sensitivities. The translation is clear enough about that.
  
• What are those 4 resistances your are talking about ? on what diagram are they ?
  

[Bogey Jammer]

Done your homework for you.

 

Introducing the SPO-15:

 

 

Details :

https://эгир.рф/pribor/stanciya-preduprezhdeniya-spo-15.html

 

Totally different beast. Supposed to be mounted on СУ-25, СУ-27, МИГ-25, МИГ-29, МИГ-31.

 

You obviously didn't put any effort to look at the documentation I provided. Don't trust youbite videos made by a random ignorant douchebag blindly buying junk from eBay.

[FoxAlfa]

Dude, are we talking about the same system ?

 

This is what I'm talking about, the damn SPO-10 complete set installed in the MiG-21bis:

 

 

 

• The video you posted clearly deals with another system. I have no idea why the guy with his stupid irritating lazy accent said it was installed in a MiG-21. That device looks like too modern to me anyway.
  
• I also don't see any reference to your L-006LM antenna anywhere in the SPO-10 documentation. If you want to talk about antennas, the only references possible are S3M-7S for the antenna itself, and S3M-8M for the adapter, nothing else.
  
• Nowhere in the SPO-10 documentation it is mentioned that each of the 4 channels has 4 sub-channels with different sensitivities. The translation is clear enough about that.
  
• What are those 4 resistances your are talking about ? on what diagram are they ?
  

 

Yes, we are but first thing you fail to accept is that SPO-10 had many versions.

 

And separate versions and hardware for each. It was installed in MiG-21s, MiG-23, MiG-25s, Tu-16, Su-7, Yak-28 etc... for bombers per example it was connected to the jammers and countermeasures.

 

I see you are referencing the manual from 1976 for SPO-10, I managed to find it but it will take some time to go trough it.

 

Myself I am referencing MiG-21 Yugoslav Military manual from 1979 in my language. It might be complete reasonable that the SPO-10 got updated and changed in the time frame difference. But at least concerning the Yugoslav L-17 (MiG-21) the SPO-10 changed the number of blips with range. Feel free to check that manual online.

[Bogey Jammer]

Yes, we are but first thing you fail to accept is that SPO-10 had many versions.

Sorry I failed what ? Your antenna was designed in the 70's, although you talked about 60's tech earlier…

 

So in the end, which sub-"version" of the SPO-10 is supposed to be modeled in DCS???

 

BTW can you send me a link to your manual please ? I have zero skill to navigate into the Balkan side of the Internet.

[Harlikwin]

While I desire to stay out of the purse swinging, I do have some background here on the technical side if you guys can get me a translated manual.

[FoxAlfa]

Hey, yeah, the miss-identification from the Youtube guy really got me before I managed to dig in to the SPO-10 manual.... I didn't expect he would be able to attain SPO-15 so easy... so much for the classified stuff...

 

Anyway, the manual you are using, page 62 11.5.6 2nd paragraph:

 

"The irradiation of a plane of any direction illuminates the corresponding light on the indicator and in tact a tone sound in the СПУ and УКР.

 

If the irradiation occurs in the search mode (pulse packs), the alarm will be triggered with the scanning frequency the antenna of the illuminating radar, and the approach of the illuminating radar the rate of the alarm will increase, and when withdrawing decrease.

 

This is because when approaching the irradiation time of the aircraft increases and the time between irradiations at the same scanning periods decreases, which gives the impression of increasing the frequency. By withdrawing occurs the opposite phenomenon.

If the illuminating radar switches to tracking mode that light alarm will be continuously"

 

 

So as the enemy approaches our aircraft is illuminated for longer time, causing the system that shows blips at constant rate to show two blips instead of one. Basically the illumination time gets longer, so it triggers second cycle instead of just one.

And as the illumination time keeps increasing eventual enters the third cycle and the three blips are seen.

Edited May 13, 2019 by FoxAlfa

[Frederf]

I don't understand how closure makes "time between irraditions" less or how this gives the impression of "more frequent sweeps." Maybe someone can explain this geometry. I understand that during tracking mode the sweep is small angles enough to "touch" on the edge of beam so naturally sweep repetition is higher.

 

This is interesting to make indication based on sweep repetition rate and not signal strength, it accounts for different radiation power in different threats. Good luck to finding out more on SPO-10 system!

[ResonantCard1]

Maybe it's the doppler effect? You receive a higher frequency than the original if the source is closing, and vice versa.

[AeriaGloria]

The radar projects a cone as the entire scanned area. The closer the radar and target are together(given same altitude), the more often the target will be inside the cone if the cone continues a steady left/right scan pattern. Maybe I’m also confused! I mean for pulse Doppler the scan is actually more of vertical 2d plane as it moves left and right. I think....

Edited May 14, 2019 by AeriaGloria

[FoxAlfa]

Yeah it got me stunned also but it makes sence. Its all to radial velocity of the sweep beam.

 

Lets say we have a search radar doing the 360 sweep and it takes 10 sec to do the sweep.

 

At 10km from the radar the beam is covering circumference of ~62,8 km in 10 sec, and traveling at 6283 m/s radial velocity

 

At 50km from the radar the beam is covering circumferences of ~314,1km in 10 sec, and

traveling at 31416 m/s radial velocity

 

Since lets say the antenna on the MiG are triggered if the that beam passes per example 100 m around the plane. The beam traveling at 6283 m/s will stay much longer in 100m trigger area then the beam traveling at 31416 m/s

Edited May 14, 2019 by FoxAlfa

[Bogey Jammer]

Anyway, the manual you are using, page 62 11.5.6 2nd paragraph:

Interesting find, I have not gone that far on my side in the translation. I guess I have to process the whole document once for all before showing up again :(

[Fri13]

The F-14s AWG 9 can literally burn it out completely at 50nm with an STT lock.

 

So AWG 9 is now the magical radar that is far more stronger than any ground radar that there is burning the SPO-10?

 

Lets be now just actually realistic, no radar can burn the RWR out. That is same kind BS that people say that in intercept missions F-14 radars were used to scare the Tu-95 rear gunners balls when the F-14 were doing intercept and went too close and the rear gunners locked the interceptors, and then F-14 turned their radars On to expose the rear gunners balls with extremely strong AWG 9 radiation.

 

First of all, the rear gunners sit in the faraday cage, so your radar can't expose them. That is one of the reasons why you are required to have all the antennas etc isolated from the fuselage and have them installed externally, instead internally, because everything inside is protected.

 

The RWR systems are designed to have infinite receiver capacity, but their limitations comes that once you are close enough or you have a emission power that is strong enough, you can saturate its capability to time the received signal. You don't burn it out, you don't damage or destroy it, you simply get it to be incapable to detect the timing difference, so it is just alarming that signal is coming from everywhere.

 

The SPO-10 is still in the classification designed to withstand even nuclear detonation EMP emissions, you can't "burn it out". And if someone claims that AWG9 does it from 100 km distance, then it is BS. As that is then a raygun that can burn out every missile, every radar, everything that is electronics.

[foxbat155]

Yes, we are but first thing you fail to accept is that SPO-10 had many versions.

 

SPO-10 had only two variants: pre 1972 and after 1972, but both have the same functionality, just part of electronic blocks were modernized in later one ( more service reliable).

System was produced in two sets: "light" for tactical aviation, and "full" for heavy machines like bombers, transport aircrafts etc.

Yak-28, Tu-16 had SPO-3 ( SPO-10's direct predecessor), Su-7 all variants had SPO-2.

[Beamscanner]

Is the SPO-10 supposed to provide PRF audio?

 

The OPs link mentioned "sound signal"

[Frederf]

Beam, no. The beep or beeps are artificial and tied to a state of how frequently the receiver is painted on the order of seconds (seconds between beam sweeping over receiver). PRF is hundreds of Hz.

 

SPO is designed in days before Doppler was common.

 

From the description the receiver isn't saturated in signal strength but in illumination events per period. For simple left-right sweep that should be constant at any range. As you get closer your illuminated time will get longer and stronger but it will still be one illumination per sweep. On the other hand multi-bar sweeping will increase the number of illuminations per sweep since at long range only one bar of the pattern will illuminate the MiG but closer other bars will also illuminate you. Maybe that's what it's designed around.