RCI 2970 Open Clarifier Mod - Need

[Wire Weasel]

Hi gang, I've done some looking around but can't immediately find this mod. May be same as would be done to 2950 but not sure. Is orange display 2970 with full-across-bottom heat sink. Not DX, Not N2, is way back plain 2970.

Need mod to open clarifier. Any hep?

Thanks!!

 

[Wire Weasel]

Found this:

Clarifier mods for CB/10 meter radios.

 

[Highlander_821]

With the VFO on that radio that tunes to 100 Hz resolution, why would you need to open the clarifier?

 

[Wire Weasel]

With the VFO on that radio that tunes to 100 Hz resolution, why would you need to open the clarifier?

Because as little as a 10 hrz difference is easily discernible to most people's ears. If the other station is say 50 hrz off, that's alot of difference and the 100hrz radio shift above or below just won't be good enough

 

[Highlander_821]

Because as little as a 10 hrz difference is easily discernible to most people's ears. If the other station is say 50 hrz off, that's alot of difference and the 100hrz radio shift above or below just won't be good enough

Yeah, but that's what the RIT is for!

 

[Robb]

Weez, that link you posted is probably correct:


RCI Ranger 2950/2970 non DX models.

This mod may work on DX models but I am not sure. I found it in my notes and could not find it anywhere on the web so here it is:
# 1. Find the clarifier harness. Find r-197. CLIP THE TOP. Do not remove.
# 2. Get a wire and solder it to the stub of wire from the resisitor. Do not solder to the resistor.
# 3. Connect other end of the wire to PIN 3 of IC6. This is the pin closest to the front of the radio.
# 4. Locate D59. It is to the left of the clarifier harness. Cut the wire part of the diode to disable.
# 5. Use L27-AM, L28-LSB, L29-USB for realignment if necessary.


Noticed that CB Tricks had 'nada' for mods on the standard 2970 non/DX page.
I'll bet that LooseCannon will know for sure.
He usually comes on the forum in the late afternoon/PST.
You might check back then.

 

[Wire Weasel]

Yeah, but that's what the RIT is for!

Yeah that's fine if there are only two people on the frequency. Say there's 3 people. Two of them have open clarifiers and go anywhere, but the other mudduck has a fixed clarifier and is 50hrz off on transmit. Now everybody can get right dead on each other and be happy ducks :drool:

 

[sp5it]

Open clarifier means track tx/rx in the same time with one knob without rx only tracking?
If so, than two guys won't tune in on SSB if they radios have misaligned tx/rx (99.9% radios are). They will try to tune one into another forever.
I prefer to track tx and rx separately.
Mike

 

[Wire Weasel]

Open clarifier means track tx/rx in the same time with one knob without rx only tracking?
If so, than two guys won't tune in on SSB if they radios have misaligned tx/rx (99.9% radios are). They will try to tune one into another forever.
I prefer to track tx and rx separately.
Mike

Of course Mike, but we're not talking about a ham rig with a continuously tunable VFO here.

Think CB sideband radio

 

[TonyV225]

Ok I could never figure out why people cut these clarifiers?? RCI 2950 chassis radios and the Uniden 2510 Chassis radios clarifiers are not even opened at the factory because that is what your shift does you can set the curser arrow on the display to change for the fine tune or coarse tune requency slide. The problem is when you cut or open these clarifiers you have set yourself up for potential frequency drifting.

I know half these radios are cut and Ive seen some that were more stable than others but the bad ones were undesirable or horrible. To each there own I guess but its easier and less work to just allign the thing internally to where you want the TX and RX if you like the 12:00 knob setting than it is to chance with cut snip jump and solder. You have to reallign anyways when clarifier mods are done.

 

[fodendaf]

people unlock their clarifiers because EVERYONE tunes by ear and especially on the rangers with a 2.5khz coverage clarifier you can't tell by looking at the clarifier knob where its recieving. Even a millimeter off makes a big difference. IMO a clarifier should be not much wider than the step size ie:100hz.Better to suffer the drift and know your on frequency than be shifting up and down for half an hour.(I'm not kidding as i've heard people going to those extremes)

 

[TonyV225]

I remember hearing some of the older Galaxy radios do that people would be talking and they were at such a drift up and down you swore they had a skipper hat on and a parrot on there shoulder!! LMAO!! :headbang

 

[fodendaf]

well the drift itself is not too bad but when someone tells you youre too low and then you move the coarse you always end up overshooting.(on channelised radios)
when you hear a conversation that ends up shifting by 10khz you know there's something wrong
I think a saw a newer galaxy with a switch to lock/unlock which is a good idea.
Methinks all small step vfo radios should have a switch to cut out the clarifier to change operation to like the magnum 257, then no-one would need to pop the covers.
The lincoln is even worse than the 2950; it's clarifier covers 6.6khz and you wouldn't have a hope of having the tx and rx lining up at 12 o clock with that.

 

[Captain Kilowatt]

Why is it only CB'ers have this problem about locked/unlocked clarifiers? Hams have used unlocked clarifiers (the big VFO knob) since the beginning, even before RIT's, and have no problems holding a roundtable with several people on the same frequency.Is it the crappy tuning and freq. alignment from the factory? Contrary to what some people say 10 Hz is not noticeable on the air. I have very good hearing, fine tuned when in the broadcast business looking for degradation of quality in the program chain and even the best engineers I know cannot tell a 10 Hz difference in spoken voice. Low frequency tones where 10 Hz is a sizeable percentage of the overall freq thay can but not when listening to spoken voice.Most ham rigs tune in 10 Hz steps and it takes a lot more than 10 Hz to be noticeable. 100 Hz is certainly noticeable but how do you know what the guy's voice is really like anyway? You tune him in until he sounds good to YOU.

 

[Wire Weasel]

Why is it only CB'ers have this problem about locked/unlocked clarifiers? Hams have used unlocked clarifiers (the big VFO knob) since the beginning, even before RIT's, and have no problems holding a roundtable with several people on the same frequency.Is it the crappy tuning and freq. alignment from the factory? Contrary to what some people say 10 Hz is not noticeable on the air. I have very good hearing, fine tuned when in the broadcast business looking for degradation of quality in the program chain and even the best engineers I know cannot tell a 10 Hz difference in spoken voice. Low frequency tones where 10 Hz is a sizeable percentage of the overall freq thay can but not when listening to spoken voice.Most ham rigs tune in 10 Hz steps and it takes a lot more than 10 Hz to be noticeable. 100 Hz is certainly noticeable but how do you know what the guy's voice is really like anyway? You tune him in until he sounds good to YOU.

Yeah that's fine if there are only two people on the frequency. Say there's 3 people. Two of them have open clarifiers and go anywhere, but the other mudduck has a fixed clarifier and is 50hrz off on transmit. Now everybody can get right dead on each other and be happy ducks :drool:

10hrz yes, 50 hrz is noticeable