Hi Guys: I recently acquired another '850 v2.0 repeater. On initial testing and tune-up, the RX section looks great; managed to tune the BPF with my TG for minimal loss and perfect symmetry, improving the RX sensitivity to provide me with 0.28uV for 12dB SINAD. Super happy with that! Next on to the transmitter and the main purpose of this post.... At first, the TX PO (Low) was providing me with 25W out, and the current draw around 9.6A. TX PO on High was around 33W, and current draw around 11.5A. The current draw is about 2A higher than what I have seen with other 850's. Initial poking and prodding around the board / Q5 / final filtering section did show some improvement in TX PO and lower current draw when I pressed upon the surface mount capacitor between the Source and Drain of Q5. I am deliberately not providing a component reference # since I cannot find the version of the board in any of the SM's that I have looked at. The Board P/No. is X45-374 0-10 A/2. That's my first request, can someone point me to the exact schematic for this particular board, please? I went on to reflow the solder around Q5. Maybe a bad move... maybe I found the issue.... Now the TX PO on both High and Low power is ~12W, and the current draw remains at 9+ Amps. Poking, pressing components, etc., makes no difference; adjusting VR1, I can reduce the TX PO, but it will not increase. Q5 does get rather hot, as does the board around the final strip. Is there a way to test the foldback circuit? Appreciate any help I can get at this point! Ramesh, VA3UV, WA3UV

Have two computer, automated technology, audio delay boards one is a DL – 1000 B the other is a DL 1000 asking $100 each plus shipping

Price lowered to $400 for the pair. This is a complete ptp link set up to 12+ km range up to 1.4 gbps throughput. Local pickup and cash in Scottsbluff NE

Looking for the measurements for UHF coupling loops. I would be most interested in the Tele wave dimensions. Working on a UHF filter project. The cavities where all 800 MHz cavities. I have already converted the “plunger” to UHF, now need to make the 800Mhz loops into UHF loops. TNX Jim Sent from Outlook

The Maratracs have been spoken for.

Got these for a 2 meter repeater project that I never found time for. 2 T73XTA7TA7BK with control heads and mics. Not sure what happened to the umbilical cables as they're not with the radios. Your only cost is for shipping. If interested contact me direct with your zip code and I can get you shipping cost. wb0vhb@...

On 12/27/2024 11:58 AM, dshack@... via groups.io wrote: Dan, I've changed the subject line, since the Sinclair Q202G is not a TX-RX duplexer and exhibits different behavior because of the way the Sinclair loop is made. Here's what Jeff said when this was observed many years ago by yours truly: "Sinclair Q202GC (not the older ones with the dielectric-tuned capacitors). Not a bad duplexer, but it is a single-loop design, with no optimization for high-pass versus low-pass. There is a very definitive shift in cavity resonance (as quantified by both return loss and insertion loss) when properly-tuned cavities are connected in cascade when the interconnect cables are optimized to maximize notch depth (i.e. nominally 1/4 wave long (14" of .66 coax). This is due to the return loss limitations of that design. Does it work? Yeah, of course. Is it optimal? No, far from it, there are other designs that are much better. Of the single-loop designs, TX-RX's is the best. It's not as ideal as a two-loop design, but those are a PITA from a mechanical standpoint." --- Jeff Please reference the attached PDF and read #3 in the "Construction Notes" section at the end of the document. This is a duplexer that utilized four of many BpBr loops that I built for Jeff. They were made from OEM band-pass loops by machining the disk / loop and installing a 30pF Johanson "type" piston trimmer using a end-mill machine. The capacitors were sourced from Bulgaria and were available on eBay for a while - more than 10 years ago. Thankfully - this duplexer's RL dips are able to be aligned 'on top of one another' after cabling the duplexer together. Notch depth optimization was achieved by using the proper lengths of cavity inter-connect cables. That carrot is also provided in the document for operation in the 2M ham band. If you need additional help understanding his exact procedure of optimizing the tuning once the cavities are cabled back together - I suggest reaching out to Jeff - either here, or directly if he's not following along. Hope this helps... Kevin W3KKC

Is there a simple configuration I can use to link 2 MTR2000s using the internal controllers without a traditional external repeater controller? Placing another Arcom or Link Comm would be overkill for this locally controlled application. Open to any ideas :) -AJ, K6LOR

Which current (or recent vintage) Motorola mobile radio will cover the UHF and VHF amateur bands without modification, and can have the wide band entitlement added without too much grief? Cheers! Martin Flynn W2RWJ

Following the troubleshooting tree in the manual, red/green alternating indicator shows stuck in boot mode and the action is to replace the SCM. 1 - Anything else we can try prior to this stage? 2 - Does this have to be from the same station (VHF hi power) or can we scavenge from the countless 800 MHz ones that became e waste? Background - Board converted to low split PA by seller in 2020, zero issues until it fell off the air last week. Power cycles no change. Swapped with spare repeater and brought back to the bench with similar red/green behavior. Thanks in advance :) AJ, K6LOR