maybe back on the air

[Pete, WA2CWA]

The 756 pro series isn't much of a receiver.  It rates a not so good spot in Rob Sherwoods's receiver performance table:

http://www.sherweng.com/table.html

Rod only sorts only on "Third-Order Dynamic Range Narrow Spaced" then the list, as viewed, is useful. If other receiver parameters are more important to you, then you have to manually figure out what is better then what based on his measurements.

[N2DTS]

I have had a pro 1, a 2 and two 3's, all were nice radios but very poor receivers.
Strong signals out of the passband caused all sorts of problems, the receiver had a lot of noise.

Nice boxes, I liked them for the ease of use and the bandscope, but good receivers they were not, they also did not TX AM well stock (it was quite bad really).

I look at two things on the Sherwood list, phase noise and the dynamic range close spaced.
If you ever get a receiver that rates high in both you will love the ability to tune something just out of the passband and have it not be there at all.

It likely matters little if you have a 90 db narrow spaced dynamic range or 100, but something like 75 or 80 is just bad.
And as far as I know, 75 or 80 is about as good as it gets with a 70 MHz first IF.

[W2NBC]

"I have had a pro 1, a 2 and two 3's" 

Why would you purchase 4 Icom Pro's if:  "good receivers they were not" ? 
 

[N2DTS]

I used them for exciters mostly, but liked the band scope.
As exciters they were great, two antenna ports, you could set one for 80 meters and the other for 40 meters, and use the RX antenna input for the band scope.
Power out was stable, the frequency was stable and accurate, the radio was easy to use.
I have since built a vfo-exciter and have an sdr-iq for the band scope.
The sdr-iq is a MUCH better receiver then the 756 pro series.

[Steve - K4HX]

If you aren't a CW contester, the rankings on the Sherwood are minimally relevant.

[N2DTS]

Not to me.
I would rather have a quiet receiver that is not bothered by a strong signal 10 or 15 Kc away.
The ratings go from really poor to very good, a very wide range.
With a good receiver, you can move 50 Hz from a strong signal and not hear it, like on 40 meters when the short wave broadcast starts in.
A signal (carrier) can be 35 db over S9 and I can not even hear if if I tune 50 Hz off.
Part of the sdr/flex radio popularity is the fact you can do stuff like that.
That does NOT work on anything with a 70 MHz first IF.

If you aren't a CW contester, the rankings on the Sherwood are minimally relevant.

[Pete, WA2CWA]

I have had a pro 1, a 2 and two 3's, all were nice radios but very poor receivers.
Strong signals out of the passband caused all sorts of problems, the receiver had a lot of noise.

Nice boxes, I liked them for the ease of use and the bandscope, but good receivers they were not, they also did not TX AM well stock (it was quite bad really).

One of the last times we talked on 40 meters (it was a Sunday morning), I was using the PRO II. You told me my audio was very good. 

[Pete, WA2CWA]

"I have had a pro 1, a 2 and two 3's" 

Why would you purchase 4 Icom Pro's if:  "good receivers they were not" ? 
 

Hey Brett, tell him how many Flex rigs you've had.

[W1RC]

Greg:

It will be good to hear you on again, man.
73,

MrMike, W1RC

[N2DTS]

Yes, you did sound good.
Not a stock radio though.
I tried the 9 volt battery thing but it did not work.
I do not know if they changed things on the pro 3 or mods were needed inside the radio.

Made a good signal generator also after making it general coverage TX by removing a few diodes...
The new 991 looks nice and the price is not bad.

I have had a pro 1, a 2 and two 3's, all were nice radios but very poor receivers.
Strong signals out of the passband caused all sorts of problems, the receiver had a lot of noise.

Nice boxes, I liked them for the ease of use and the bandscope, but good receivers they were not, they also did not TX AM well stock (it was quite bad really).

One of the last times we talked on 40 meters (it was a Sunday morning), I was using the PRO II. You told me my audio was very good. 

[N2DTS]

The Ten Tec eagle seems to get high marks in everything:


 Pure joy QSK CW operation, like the other TT rigs I've had, and still have. But on voice modes it's also pretty amazing. I used it to make some 10m AM contacts over the past couple of weeks and the older, experienced ops asked me how big a boat anchor I was using because it sounded like a KW-1 or similar. Amazing fullness and fidelity, and actually better modulation that my old Viking Ranger.

Looks a lot like my Argonaut 5, lower price also ($1499.00).
30 day free trial, I may actually try one...really good reviews.

[Pete, WA2CWA]

Yes, you did sound good.
Not a stock radio though.
I tried the 9 volt battery thing but it did not work.
I do not know if they changed things on the pro 3 or mods were needed inside the radio.

Made a good signal generator also after making it general coverage TX by removing a few diodes...
The new 991 looks nice and the price is not bad.

I have had a pro 1, a 2 and two 3's, all were nice radios but very poor receivers.
Strong signals out of the passband caused all sorts of problems, the receiver had a lot of noise.

Nice boxes, I liked them for the ease of use and the bandscope, but good receivers they were not, they also did not TX AM well stock (it was quite bad really).

One of the last times we talked on 40 meters (it was a Sunday morning), I was using the PRO II. You told me my audio was very good.  

The rig is all stock. The only difference is I use the audio input to the modulator directly at the ACC1 socket on the rear panel. Bypasses all the audio tailoring that Icom does from the mike jack to the modulator.

[w1vtp]

I'll have to respectfully disagree with the comments that Rob's list, especially Dynamic Range Narrow Spaced (dB) spec. are only of interest to CW contesters.  When one is dealing with a very strong adjacent signal (the one you don't want to hear) that is actually out of the passband of the station of interest - especially when that station of interest is relatively weak in comparison the sideband products of the adjacent strong signal then good dynamic range becomes very important.

Receivers with relatively poor performance will be affected by a cross modulation of the strong station imposing itself on the station you want to hear.  That's where the high performance receivers really pay off.  High performance in the high dynamic range narrow spaced specification makes all the difference in the world.  IF filters are not the only tool against this sort of problem that is sometimes call "splatter."  Receivers with poor narrow spaced specs will perform poorly in the CW, AM, and SSB mode when it is presented with a very strong signal that is out of the IF filter passband but still close enough to cross modulate the weak signal.  So this receiver not only presents to the listener the sideband products of the unwanted signal but also the cross modulation products resulting from poor narrow spaced performance.

Al

 

[N2DTS]

Another thing is the AGC.
If you have a 1st IF 15+ KHz wide to support FM mode (with a poor filter at 70 MHz), a strong signal 10 Kc away from what you are listening to will pump the AGC up in that 1st IF and hose up the weak signal you are trying to copy.
All the PRO series had one 15 KHz filter in the 70 MHz IF, some newer radios tried switching in different filters, but 70 MHz narrow filters do not work well at all.

Some companies are moving to a 9 MHz 1st IF, Elecraft and Ten Tec, and the FTDX 5000.
I would think any brand new radio would go that way.

Id you look at the Ten Tec eagle, its got switched 1st IF filters at 9 MHz, very low LO (phase) noise, and has quite good spec's. It gets great reviews for a quiet well working RX and easy to listen to audio, people rave about it. No one raves about any icom audio...

[w1vtp]

Greg

We kinda got off topic, didn't we?  Congrats on the purchase of the FT-991 and good operating and good listening.

What bands are you going to be on?  Antennas?  Maybe a bit off topic but at any rate, looking forward to a QSO with you soon.  I'm on 75 & 40

GL, Al

[W3GMS]

just bought new ft991 - not sure if i can work it - no tubes any comments?  - greg

Greg,

Nice to hear your getting back on the air. 

Amazing what this thread has started. 

Joe GMS

[w1vtp]

just bought new ft991 - not sure if i can work it - no tubes any comments?  - greg

Greg,

Nice to hear your getting back on the air. 

Amazing what this thread has started. 

Joe GMS

 

[Steve - K4HX]

Tell me how a signal 15 kHz away relates to the Sherwood rankings. They are based on 2 kHz spacing. Now you are trying to tell us this relates to 50 Hz spacing. Really?

Not to me.
I would rather have a quiet receiver that is not bothered by a strong signal 10 or 15 Kc away.
The ratings go from really poor to very good, a very wide range.
With a good receiver, you can move 50 Hz from a strong signal and not hear it, like on 40 meters when the short wave broadcast starts in.
A signal (carrier) can be 35 db over S9 and I can not even hear if if I tune 50 Hz off.
Part of the sdr/flex radio popularity is the fact you can do stuff like that.
That does NOT work on anything with a 70 MHz first IF.

If you aren't a CW contester, the rankings on the Sherwood are minimally relevant.

[N2DTS]

He rates them close and wide spaced.
If something is poor wide spaced, it can not be good narrow spaced.
Most SDR's have the same wide and narrow space ratings, and that goes well beyond 2 KHz to 20 Hz.
So you can have a super strong signal just out of the passband and not know its there at all.

With a good receiver, it does not matter what is going on 15 KHz away, or 2 KHz, or 50 Hz.
I have had some of the top receivers on the list 7, 13, 15 and plenty of ones not so high on the list.



 

[n1exi]

i wanted to get the biggest bang for the bux - 160 - 440 - am ssb - cw - lightweight - maybe some mod later greg - n1exi

[n1exi]

gms - rc and all others - tnx - always can count on am community for support - and kudos - greg - n1exi

[KD6VXI]

Greg,

As I said,  I have the previous iteration.   I'm happy,  and jumped on it for the same reason.   It did everything,  everywhere

I do,  however,  find ham radio deluxe being a GREAT companion to the radio for home use.   Lots of controls brought out of the menus and to the display for easy use.

I also have the yeasu programming software.   Makes v/uhf repeater programming much easier.

Enjoy....   I do mine.  

--Shane
KD6VXI

[n1exi]

tnx shane - looking for modulation on the air - i am of the opinion that whatever rig you using does not matter - it is the content - the one behind the mike - greg n1exi

[Steve - K4HX]

You didn't answer any of my questions. Instead of further high jacking this thread, I've started another one on the subject of Receiver IMD in the Tech section.

http://amfone.net/Amforum/index.php?topic=37820.0

He rates them close and wide spaced.
If something is poor wide spaced, it can not be good narrow spaced.
Most SDR's have the same wide and narrow space ratings, and that goes well beyond 2 KHz to 20 Hz.
So you can have a super strong signal just out of the passband and not know its there at all.

With a good receiver, it does not matter what is going on 15 KHz away, or 2 KHz, or 50 Hz.
I have had some of the top receivers on the list 7, 13, 15 and plenty of ones not so high on the list.



 

[n1exi]

just need new coax - local radio shack still in biz and has rolls of 52 ohm - want all new - price is right and always can up grade - scared - new rig and i don't wanna screw up - been there - done that!
greg - n1ex1