Ranger RCI 2990

[nomadradio]

The shaft on those controls is longer than any catalog part has. One dodge is to use a 12mm metric pot with a short shaft, mounted directly to the front panel. Just one problem. The length of the control's threaded bushing may be too short to reach through the thick panel. Countersinking the hole in the face of the front panel large enough for the control's shaft nut would allow using a control with a short bushing, but I'm not enough of a machinist to try that yet. Mouser still had controls like that, and we get them from fleabay vendors. Tricky part is to get with with a proper audio taper.

I checked Barkett, and he no longer has anything even similar listed. Gotta figure he runs out of the most-popular parts first. Next time I'm at work I'll look for the Mouser part number for a 50k volume pot with a short 6mm split shaft.

73

 

[Raccoon]

The shaft on those controls is longer than any catalog part has. One dodge is to use a 12mm metric pot with a short shaft, mounted directly to the front panel. Just one problem. The length of the control's threaded bushing may be too short to reach through the thick panel. Countersinking the hole in the face of the front panel large enough for the control's shaft nut would allow using a control with a short bushing, but I'm not enough of a machinist to try that yet. Mouser still had controls like that, and we get them from fleabay vendors. Tricky part is to get with with a proper audio taper.

I checked Barkett, and he no longer has anything even similar listed. Gotta figure he runs out of the most-popular parts first. Next time I'm at work I'll look for the Mouser part number for a 50k volume pot with a short 6mm split shaft.

73

I ordered one from Barkett that says it's the right replacement part for the 2990 Volume Switch . It says : "Potentiometer 50KA / RF Power DX22/2517 RCI-2990 Replacement" ... did I order the wrong part ??

It looked like the right part.

​

 

[nomadradio]

Holy moly! I sure missed that when I looked there. Probably ought to buy some for that proverbial rainy day.

73

 

[Raccoon]

Holy moly! I sure missed that when I looked there. Probably ought to buy some for that proverbial rainy day.

73

Nomad, do you happen to know which parts control the transmit audio in the 2990 ? At least a place where I can start poking around to see if I can fix it's transmit problem. When you first key it up it sounds fine. But when you're talking if you use words with letters like "K/C", "T", or "S" in them , something that will peak the audio ... it instantly makes an over powering , and annoying noise that makes it sound like the audio is over driven. If I unkey, and key back up again ... it's gone until I use another word with one of those letters again. I've never owned a 2990 before, so I have no idea where to even start looking in this radio.

 

[Shadetree Mechanic]

The shaft on those controls is longer than any catalog part has. One dodge is to use a 12mm metric pot with a short shaft, mounted directly to the front panel. Just one problem. The length of the control's threaded bushing may be too short to reach through the thick panel. Countersinking the hole in the face of the front panel large enough for the control's shaft nut would allow using a control with a short bushing, but I'm not enough of a machinist to try that yet. Mouser still had controls like that, and we get them from fleabay vendors. Tricky part is to get with with a proper audio taper.

I checked Barkett, and he no longer has anything even similar listed. Gotta figure he runs out of the most-popular parts first. Next time I'm at work I'll look for the Mouser part number for a 50k volume pot with a short 6mm split shaft.

73

Something like this works well with a drill press for counterboring.

Akozon 5pcs M3-M8 Slotting Counterbore End Mill Cutter Solid Slot Countersink End Mill Drill Bit https://a.co/d/iRvwiO3

 

[BayouRadioAmplifier]

But when you're talking if you use words with letters like "K/C", "T", or "S" in them , something that will peak the audio ... it instantly makes an over powering , and annoying noise that makes it sound like the audio is over driven. If I unkey, and key back up again ... it's gone until I use another word with one of those letters again. I've never owned a 2990 before, so I have no idea where to even start looking in this radio.

oh, I just did some quick research on that 2990. It has the same boards inside
as on the old 2970 I was just repairing.

So that TX problem in AM or SSB?
Using a battery powered pre-amp mic?

in AM turn carrier power down to just over 30 Watts.
So capable to do 120 to 140 W PEP out.
I set this 2970 inside so he can't turn it up to 75 Watts
carrier, cause I know he will do that! ! !

The extra RF PA board has an odd bias adjustment.
This one here had the T/R relay changed. This
messes with the bias circuit also. Bias was up
to 7 Amps! Had to change a few resistors.

 

[Raccoon]

2990 Update : My replacement switch for the AF Gain arrived from Barkett arrived, and I replaced it . The audio still cuts out occasionally , but if I turn it up and back down real quick it usually fixes it. I might need to spray it out with some cleaner, I'm not sure.

The transmit is still acting up when I'm talking on it. At first it sounds fine, but then when a say something that pushes the audio level to it's peak it instantly makes an over powering noise that makes it sound like the audio is over driven. If I unkey, and key back up again ... it's gone until I say something that pushes the audio level again.

The signal and SWR meters are still both stuck ... despite the radio being on for weeks now.

This isn't one of those 2990's that's been through the hands of hundreds of people and screw drivered to death by everyone ... it was my Mom's. She bought it new and she babied it for the past 30 (plus) years . If it needed anything done to it, it always went to an experienced tech. But when her antenna broke about 10-15 years ago ... she stopped turning it on. So it's just been sitting for all of that time, until I got it about a month ago. It has it's quirks , and somedays it drive me nuts. But it was my Mom's and I'm just trying to get it back on it's feet again .

I do greatly appreciate all of the help and information that you've all given me so far.