R2670B Poor Over the air and no audio

adamr368

Regular Member
CS Forums $upporter
Joined
Oct 5, 2020
Messages
22
Hi, all: Working on an R2670B that seems to be in great shape with lots of options. Unfortunately, this unit has no audio from the speaker, but you can hear it if you connect a speaker to the Demod out port. Also, the sensitivity is very weak over the air. I replaced the fuses in the antenna connector and generate connector and all of the generate functions appear to work fine, as does receive via the I/O port, but not so much on the antenna port. Any thoughts on where I can look, or is it time to cut my losses or does this seem like something that can be repaired? Thanks!
 

d119

Prolific Contributor
CS Forums $upporter
Joined
May 22, 2012
Messages
959
Anything can be repaired. Stupid question I know, but you have verified that when trying to receive off the air with the antenna port that the attenuator is set to 0, correct?
 
OP
A

adamr368

Regular Member
CS Forums $upporter
Joined
Oct 5, 2020
Messages
22
Anything can be repaired. Stupid question I know, but you have verified that when trying to receive off the air with the antenna port that the attenuator is set to 0, correct?
Hi - thanks for the reply. Yes, I have a 2600B as well (until it sells) so I am familiar with the operation. I quickly realized this was over my head and decided to send the unit to JRY (Cin-Com) for repair - and I am really happy that I did so. The turnaround was lightning quick and I'll receive the unit back exactly one week to the day that I shipped it out - incredible! The estimate was fair and the actual cost came in at exactly the quoted price. Sorry if I turned this into a ringing endorsement, but there's likely an element of concern when you consider shipping someone you met on an internet board a multi-thousand dollar piece of equipment and cross your fingers that you'll get it back :)
 

wiredwrx

Prolific Contributor
CS Forums $upporter
Joined
Mar 20, 2014
Messages
648
Hi - thanks for the reply. Yes, I have a 2600B as well (until it sells) so I am familiar with the operation. I quickly realized this was over my head and decided to send the unit to JRY (Cin-Com) for repair - and I am really happy that I did so. The turnaround was lightning quick and I'll receive the unit back exactly one week to the day that I shipped it out - incredible! The estimate was fair and the actual cost came in at exactly the quoted price. Sorry if I turned this into a ringing endorsement, but there's likely an element of concern when you consider shipping someone you met on an internet board a multi-thousand dollar piece of equipment and cross your fingers that you'll get it back :)
What did JRY say it was?
 

jry

Prolific Contributor
CS Forums $upporter
Joined
Mar 4, 2012
Messages
263
the audio issue was with a coupling cap on the processor board.

the rf input issue ended up replacing the protection diodes and RF switch. ( easier said than done due to the new and improved shield used on the later version )

and OBTW do NOT use anything other than 1/16 amp fuses. Wasn't the issue on this when I got it but just got one in with the wrong fuse on the antenna port and it's typical to see these come in with multi AMP rated fuses used which will really cause even more damage if keyed into

If you are really dire straights use a 1/4 watt 5.6 ohm resistor ...it's what IFR buried in the IF block on some of their classics. The normal resistance of the 1/16 pico is about six ohms so it's not like you are throwing things off.