Maxtrac squelch slow to open

[vhacmowilmob]

I just got another Maxtrac 300 UHF (449-470). I have about 10 of these in service as echolink/IRLP links around the state, and this is the first one that's given me this issue...

(It's not interfaced yet, so it shouldn't be a problem, as I take unsquelched audio from the interface connector, but...)
The squelch seems to take forever to open on receiving a signal. The receiver opens with a 225.7hz CTCSS, and takes more than 1/2second to open on TX from my HT. The other radios are nearly instant.
Programming is the same on all, except for frequency, and I can't figure out what's wrong here.

I haven't put the radio on the communications analyzer yet, but my frequency counter shows the radio is only about 600hz off frequency (I've seen worse), so the oscillator should be OK. I don't know what else to look for.

Any suggestions?
TNX
Brad
W0VHA

[CircleBat]

Squelch is turned up too high.. its one of the blue pots tht you manually turn down..

[com501]

Check the VCO voltage to make sure it is well within the range for lockup. If its on the edge, lockup times can be very slow.

[Bill_G]

Could be a case of the board pins too - those pins between the logic and rf brd.

[Will]

There is mod for Maxtrac and Radius mobile, squelch slow to open. I will have to look it up and post it.

[vhacmowilmob]

I checked the squelch, and it's set properly. I'll take the radio in to work tonight and check the VCO (and clean the pins) and see what happens.

[vhacmowilmob]

Checked out the radio this morning...
VCOs are both right where they should be, and I cleaned all connectors, including the interboard one.
Oscillator reference has been adjusted to within 20hz.
Squelch is set properly. Squelch opens at ~0.2uV, but takes its time doing it.

Maybe I just have a slow radio...

[Will]

Maybe I just have a slow radio...

You need to do a mod to get faster un-mute. Are you into removing and replacing two small parts in your Maxtrac?

[Bill_G]

Maybe I just have a slow radio...

You need to do a mod to get faster un-mute. Are you into removing and replacing two small parts in your Maxtrac?

Let me guess - a couple feedback caps on the squelch chip? Or on the mute gate? or both.

[vhacmowilmob]

Maybe I just have a slow radio...

You need to do a mod to get faster un-mute. Are you into removing and replacing two small parts in your Maxtrac?

If they're not SMT, I can do it... (my vision isn't good enough to play with SMT parts, even with the CCTV camera)

[vhacmowilmob]

Will,
Can you post a link (or instructions) for this squelch mod? I have another (VHF) maxtrac with the same issue...
TNX
W0VHA