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Peter, I have changed out all electrolytics in accordeance with a capacitor parts list provided by Jim. No Capar, mixed brands. Well ... yes, hopefully. All new caps tested before installing? for

Here is a photo of my RV-75 which is set for a TR7. So yours seems to be ok. Some where I have some notes on the position so will have to look. 73? Bob

Rick: FWIW...I notice you have different electrolytic caps in there - i.e. not CAPAR? Do they look original, I wonder, or have they been changed? If so...hopefully all done correctly! Jim can confirm,

Clint, Havent done this yet but its next on my list. But a bit of confusion here. The RV75 manual Section 5-5.3 REFERENCE OSCILLATOR ADJUSTMENT calls for a freq of 1.280000 MHz AT tp114, while your

I'll do this but after reviewing the complete alignment procedue in the manual, I'll also step through this to see if my unit is properly aligned (without making any adjustments). If it is not close,

Could it be that there is a programming arrangement somewhere on the board that selects the offset? Maybe a resistor jumper somewhere that has been installed? 73, Clint, VE3CMQ

Hi Rick. Have you checked the reference oscillator frequency? It doesn’t take much for this to put the entire system out of wack. It’s frequency should be 5.12MHz exactly. This is on the digital

Thanks for the all info Jim, Yes, my TR7 has the fan fitted. 73, Dave

It sounds like the PLL is not locked. Check the VCO voltage. It should be between 4.5 and 7.5 Volts, stable, and move when you turn the main tuning knob. 73 -Jim NU0C "Rick K8EZB"

Thanks, Jim. Yes, lucky for me! I have done some additional troubleshooting. The good news: static power supply regulation seems to be right on on both boards: 13v, 9v, and 5v, all well within Drake

Jim Thank you for your comments. Very helpful. And than you to Dave for raising the topic. I know now the cheap options with mine. Nigel

They all have some small amount of drift. How much depends partly on how well the PTO has aged and the accuracy of the factory temperature compensation. I found that mine have been plenty stable

Lucky for you that I took good pictures of mine. :) As found, set for 7 line. 73 -Jim NU0C "Rick K8EZB" <frboswell@...> wrote:

It bears noting that the original specification for frequency stability for the TR7 is less than 1 kHz during the first hour and less than 150 Hz / hr thereafter. I know that we have all become spoilt

Update: Further testing in accordance with manual checkout procedures indicates a possible digital board issue unrelated to the previously identified freq drift problem. Before I take the

Ken that it does. I get the 1.6mHz offset. Never gave it any thought about 220. The one I’m working on does not have the 220 board. However, the offset board might think it does. Good info mike

Hi Mike, You are getting a 1.6 MHz offset. That is the offset that is normally used on 220 MHz. Is it possible that somehow (don't ask me how) that the crazy thing thinks you are on 220 MHz and gives

Although I promised myself I’d never work on one of these UV3s again… I can’t say that anymore The one I have on my bench has a weird problem with the transmit offset. I set the dial to the

I also recently acquired a loaded TR-7. It came with a German version of a VFO stabilizer, and it keeps the TR-7 within 10Hz from dead cold start. Elcon is making the Elcon 34 frequency stabilizer. I

Hi, New to the forum here. I've had a C line for some time but recently have got a TR7. From switch on, there is a gradual slow drift downwards in frequency of both transmit and receive. During short