Batboard

Picked up an R2660C on eBay for $575.. Made an offer and got lucky.

Seems to work fairly well, but there are a couple of oddities I have noticed:

1. It seems to show a random signal level when nothing is being input. Doesn't show a frequency error when its doing this, nor a deviation. It measures signal level normally when one is injected.

2. Tracking generator dynamic range seems to be about -90dBm. That seem right?

3. When first turned on, the audio generator (PL) drops out a bit then stabilizes.

I would imagine this unit is going to need capacitors replaced. Where to begin with that? The display is in excellent condition (as it the unit itself), seems to have been used, but not abused if you know what I mean.

Display has excellent brightness range, no burn-in. Date code of the display matches the monitor (1998).

Nothing inside looks futzed with.

I welcome any commentary or suggestion. I have the option of returning the unit for a refund, but I know I won't find another at this price, and aside from that, I'm not looking for perfection, just the ability to tune duplexers and radios with a reasonable degree of accuracy.

I compared everything else against a calibrated R2670D, and didn't find anything shocking other than the TG dynamic range.

on all of the R26XX series I always start by doing a NVRAM reset which forces a full calibration.

The R26XX is heavily software driven and dependent on values calculated in the calibration routine,

After that compare to your known good unit

Very good. I assume that is done in the SPF menu?

Additionally, I have ordered a replacement battery for the unit, where is that battery located and is it reasonably accessible?

Thanks!

I have swapped the batteries without pulling the processor but I have done over a hundred of these units over the years .

You may want to pull the card ...remember it goes on the non component side when you re-install.

Yes the NVRAM clear is under the SPF and System Functions

OK. Ran the NVRAM clear and recalibrated. Still getting random signal level numbers. Checked against an IFR-A7550 that hasn't seen a calibration in God knows how long, it's reasonably accurate though.

One thing I do hear a bit of is a sweeping carrier in the background of the demodulated carrier... Any thoughts on that?

so I would look at the outputs of the LO's .... the R26XX uses a number of these even on just the monitor side.
It may be that one of them is having a hard time locking.

Look at the service manual ...you will need an SA that covers up to 2 or 3 Ghz for the higher frequency ones.

You can look at the "noise" level on generate.

The residual AM and FM levels are specified in the service manual.

I usually use an 8902A to check this but you can use another service monitor if it's really bad.

It appears that the noise floor on this machine is around -90 in the spectrum analyzer.

Do you work on these? Whats the ballpark cost? This is an amateur radio use unit, no profit made with it.

d119 wrote: ↑

Tue Nov 19, 2019 8:52 am

Very good. I assume that is done in the SPF menu?

Additionally, I have ordered a replacement battery for the unit, where is that battery located and is it reasonably accessible?

Thanks!

God only knows how long the battery is thats in my EBAY 2670. I'm in a bit of a panic to get the old one out and a new one in. Does anyone have a source and part number for this beast?

W0VNE wrote: ↑

Wed Feb 07, 2024 9:51 am

d119 wrote: ↑

Tue Nov 19, 2019 8:52 am

Very good. I assume that is done in the SPF menu?

Additionally, I have ordered a replacement battery for the unit, where is that battery located and is it reasonably accessible?

Thanks!

God only knows how long the battery is thats in my EBAY 2670. I'm in a bit of a panic to get the old one out and a new one in. Does anyone have a source and part number for this beast?

Some good discussion recently over on the Repeater Builder group on groups.io about this very subject. jry here on the board is extremely knowledgeable as well.