SP-1a Speech Processor

[Handy Andy]

Hi! Welcome to Cooking With RF...

Todays' Topic, Audio Compression - can it speed up cooking time?

... (Dot Dot Dot)...

So, yes it does add heat, so be sure to set the timer - for best results in even cooking, remember to turn them over....

IF you use cheap finals - that's one thing - Unobtainium type of Finals are another...

One direction, the sky's the limit you just replace the blown finals and support parts and try again with a different setting until you find your right balance...

OR the other direction is to keep it simple and try not to ride the Mic gains too hot on audio application which translates into extra heat they will have to dissipate else the heat will destroy the parts...

 

[Captain Kilowatt]

Ok, I have been doing as much research on this speech processor as I possibly can. So far, the general consensus is that it is a benefit on SSB. My question is will this tax the finals more than say doing the NPC/RC mod & volting the final?
Any info would be greatly appreciated. I will probably go ahead & pick up one of these SP-1A anyways, I'd just like to know If I should keep an eye on the final.
Thank you for your time & knowledge.
Walterjn

I have one in a 2950DX and it works great if properly adjusted. As with anything if over driven it will sound like crap and cause overheating. Just donot over do things on set up and you will be fine.

 

[walterjn]

I have one in a 2950DX and it works great if properly adjusted. As with anything if over driven it will sound like crap and cause overheating. Just donot over do things on set up and you will be fine.

I go for clean sound, ALWAYS have. I personally would prefer to have a clean, undistorted audio to anything else.

 

[Onelasttime]

Ok, I have been doing as much research on this speech processor as I possibly can. So far, the general consensus is that it is a benefit on SSB. My question is will this tax the finals more than say doing the NPC/RC mod & volting the final?
Any info would be greatly appreciated. I will probably go ahead & pick up one of these SP-1A anyways, I'd just like to know If I should keep an eye on the final.
Thank you for your time & knowledge.
Walterjn

Yes it will tax the radio more than running stock. That said I have never seen and NPC red wire mod that did not tax the heck out of not only the modified parts but the entire radio. I do not think anything taxes a radio like the NPC and Red Wire Mod. Everytime you make a mod to a radio you push the failure mod up or down the chain to a place the engineers never expected would be an issue. If people used moderation it might be different but no one want 115%, 120% or 140% modulation they want 200%.....No one runs it sometimes they run it all of the time! No one ever does a system that is actively and dynamicly controlling the AGC with more precission and sophistication it is always a move backwards.

Things like the SP1-a are not going to make your radio hot enough to light a cigar. You regulators will not be burning hot and your finals will not need to be strapped/volted/red wire mod. The SP1-a has a lead for a switch so you can easily turn it on and off. Most NPC mods even when a switch is installed it is still altering the circuit drastically when switched off in most cases. Do not even get me started on how poorly 99% of NPC mod's are done and all the impedance issues what a ball of wax!

 

[711]

Heart of the SP1a is the NE571 compander.

 

[Captain Kilowatt]

Yes it will tax the radio more than running stock. That said I have never seen and NPC red wire mod that did not tax the heck out of not only the modified parts but the entire radio. I do not think anything taxes a radio like the NPC and Red Wire Mod. Everytime you make a mod to a radio you push the failure mod up or down the chain to a place the engineers never expected would be an issue. If people used moderation it might be different but no one want 115%, 120% or 140% modulation they want 200%.....No one runs it sometimes they run it all of the time! No one ever does a system that is actively and dynamicly controlling the AGC with more precission and sophistication it is always a move backwards.

Things like the SP1-a are not going to make your radio hot enough to light a cigar. You regulators will not be burning hot and your finals will not need to be strapped/volted/red wire mod. The SP1-a has a lead for a switch so you can easily turn it on and off. Most NPC mods even when a switch is installed it is still altering the circuit drastically when switched off in most cases. Do not even get me started on how poorly 99% of NPC mod's are done and all the impedance issues what a ball of wax!

I agree 100%. I do have an SP1-A installed in a 2950DX and it does have a switch. I have it set so that it does make a noticeable difference yet does not overdrive the radio. I actually got good reports from it. I also have another SP1-A installed in a small project box that I use after my mike preamp and EQ when driving my Heath DX-60B on AM.

 

[Redbeard U812]

I agree 100%. I do have an SP1-A installed in a 2950DX and it does have a switch. I have it set so that it does make a noticeable difference yet does not overdrive the radio. I actually got good reports from it. I also have another SP1-A installed in a small project box that I use after my mike preamp and EQ when driving my Heath DX-60B on AM.

So they can be used sparingly and have good results. Kav wants to remove his entirely from a 148. I tried to explain it was probably good for SSB but not advisable for AM. Would it be better to leave it in?

 

[Captain Kilowatt]

So they can be used sparingly and have good results. Kav wants to remove his entirely from a 148. I tried to explain it was probably good for SSB but not advisable for AM. Would it be better to leave it in?

If it works than sure leave it in. Just don't crank the level and compression pots up all the way. I find it gives me just a nice boost in audio on the old Heath DX-60B. I don't push it too hard and use it mainly for the compression as the Heath has plenty of audio gain itself.

 

[Redbeard U812]

If it works than sure leave it in. Just don't crank the level and compression pots up all the way. I find it gives me just a nice boost in audio on the old Heath DX-60B. I don't push it too hard and use it mainly for the compression as the Heath has plenty of audio gain itself.

Coming from someone who runs one or two he may be convinced to leave it in. Every time he decides to "work" on a radio, it get wacked out and ends up in the barn.

Thanks, I'll let him know it's good.

 

[Onelasttime]

Hi! Welcome to Cooking With RF...

Todays' Topic, Audio Compression - can it speed up cooking time?

... (Dot Dot Dot)...

So, yes it does add heat, so be sure to set the timer - for best results in even cooking, remember to turn them over....

IF you use cheap finals - that's one thing - Unobtainium type of Finals are another...

One direction, the sky's the limit you just replace the blown finals and support parts and try again with a different setting until you find your right balance...

OR the other direction is to keep it simple and try not to ride the Mic gains too hot on audio application which translates into extra heat they will have to dissipate else the heat will destroy the parts...

If a radio is properly set up you should have no problem running with the front panel mic gain control turned all the way up. If the radio has been butchered or setup by a butcher only then does one end up a radio that can not run clean and clear with mic gain cranked all the way up! Same is true for RF power control on the front of a radio. If the radio is properly aligned you should be able to run it at full power and not have issues. No radio would ever leave a factory (not talking about modern Chinese made export and cb radios)with such a poorly thought out alignment that would stress the radio beyond the factory rating when turned up all the way on the face. When modern ones do that shows the lack of Quality Control by the Chinese manufacture! If your radio or amplifier is not going 20+ years with out blowing parts you need to either leave the radio alone or find a better technician to align it for you!

 

[TheRealPorkchop]

Heart of the SP1a is the NE571 compander.
View attachment 28930

Too bad we don’t have the schematic for that. Easy enough to clone I guess. I don’t see a 571 there though.

 

[kopcicle]

Too bad we don’t have the schematic for that

 

[711]

Too bad we don’t have the schematic for that. Easy enough to clone I guess. I don’t see a 571 there though.

I removed the 571 and made a surface mount clone of this board. Made my own schematic packed away somewhere

 

[TheRealPorkchop]

Nice.

 

[711]

I need to learn how to do dual sided boards lol