Thanks to all for your response---but I neglected to mention that the rig has been working FB over the years, and yes---I have the 10-turn pot, as well as the Digital Dial---all in 'good order'. The fact that I can hear the relay of an 'outboard' keyer when I use the hand-key tells me that something is working in the transmitter circuit---I believe---

I just cannot fathom how the transmit portion suddenly stopped working---and the fact that I consider myself somewhat 'technically-challenged'---adds to my dilemma.

The final output transistor is a C2078.

Ernie
VE3GNU

Help Wanted!
What's the easiest way to trouble-shoot or check the transmitter of my QRP OHR100 rig?
The receiver works fine, and I hear the CW sidetone alright when I key the transmitter, but no RF out---no voltage out!
Can I assume that the FINAL transmitter is 'shot' or is that too simplistic?
The manual provides no voltage checks on the schematic diagram and no voltage-check chart is available.
Thanks in advance---and much appreciated.
73---Ernie
VE3GNU

My Icom 740 (bought in '82 this month) has every conceivable knob, button, and sliders for all functions. Not only are the knobs still as smooth and positive as when new, but they also have stainless steel 'skirts!  The 'mode', 'band' and 'meter' knobs are of the kind used on Drake gear! The true analog meter has 6 functions.  The 'AGC' knob is variable from 'off' to 'fast' to 'slow', the 'noise blanker' knob can be used from 'off' to 'normal' to 'wide' and a secondary knob can be adjusted to 'level'.
The VFO knob is every bit as smooth when new---its speed can be selected from '1 khz' to '100 khz' to '10 khz'.
I have it equipped with the FM board (haven't used that for a long while), the electronic keyer board (replaced by an outboard keyer), 2 Inrad filters for SSB, and the Icom 500 Hz CW filter.
Over the past years I have considered buying a replacement, but the longer I hold off, the more I intend on keeping it.
From what I have read---only about 4000 were built.  It has no 'general coverage'---a fact that may have hastened its demise----
I am contributing this posting all 'in the interest of KNOBS----may they stay forever!

I have the Begali Simplex Professional---with the black base and the red finger pieces, and it's perfect for me.
Ernie
VE3GNU

When I returned to CW after many years of neglect---and after building a few kit QRP rigs, I opted for the Idiom Press CMOS-4 keyer and have found it really excellent----it has the memory functions, but it required that I keep its manual handy.  The next keyer I bought was the Palstar CW50A keyer---also an excellent and well-built keyer---one with very accessible functions right 'up front'---i.e. 'Speed', 'Volume', 'Pitch'----as well as 'Tune' for the transmitter.  Both external keyers easily surpass the expensive keyer-board in my Icom 740---
73---Ernie

Google:   QRPer----and scroll down to the latest interview done with John Henry---TenTec Engineering---

Assembled my own CMOS-4 a number of years ago to use with my kit-built QRP rigs---works great, easy on the batteries, and it's wise to keep the manual handy---in the event changes in settings are needed after you haven't used it for a while.
73---Ernie VE3GNU

I, too, have had excellent experiences with Idiom Press over the years---have bought the CMOS-4 keyer and the SCAF-1 Filter---both of which I have assembled from Kits.
An excellent company with which to deal.
73---Ernie
VE3GNU

Dave----I second the suggestion of the Wilderness NC-40A---a wonderful monoband kit with clear and easy-to-understand instructions---fantastic receiver with narrow bandpass!
As well, consider the Ten Tec 1340 Kit---more parts, bigger and heavier, more challenging to build, but a 'hot' receiver with wonderful QSK.
Also have the OHR-100A for 20m---more features, easier to build than the TT, but with a more spacious board.
GL with your choice.
Ernie  VE3GNU

Thank you for the additional input: Charles, Frank, and Bob----all very informative and relevant to my query.  In addition, I would like to add to the comment from Barry---i.e. "---the TS480SAT is the best performing radio you can get for under $1000.00 US".----Well, I can only dream----since the radio is listed currently at Radio World in Toronto for $1300.00---plus the sales tax of $169.00, bringing the total to $1469.00 CAN.---bringing it up to the under $1500.00 category---and that's not including shipping or filters!  In fairness to Radio World, though, it offers a 2-year warranty on the radio.
I appreciate everyone's input.
73---Ernie
VE3GNU

KU3X and W8JX---Thank you for this,  and the confirmation on the rigs as far as their 'performance'--- as well, I continue to seek feedback for those operators who have had both rigs and who can tell me about their experience with respect to the 'sound' of the incoming signals on both.
Thanks es73---
Ernie VE3GNU

KK7KZ---That's exactly the kind of answer I was hoping to get---and thank you for detailing your experience with both rigs. 
Anyone else, please chime in if you can----
73---Ernie
VE3GNU

Hello---Given that the Icom 7200 is a newer and IF DSP design and that the Kenwood TS480 is an older and AF DSP design---when it comes to the 'bottom line' of which is the 'best and quietest', I welcome the feedback from any one having had both and is able to render an honest opinion based on the essential 'receiver' parameters that I'm interested in---i.e. selectivity, quietness, easy-on-the-ears---and possibly closest to the analog sound that I get from my 30 year-old Icom 740.  All and any feedback is welcome and appreciated.  Thanks in advance.
73---Ernie
VE3GNU

Bill---Have a look at the Palstar Keyer---model CW50A.  It has all the functions on the front panel that you need---i.e. Speed, Volume, and Pitch, Power, Tune.
It's a 'stand-alone' model that can be powered by a 9V battery---is well-built and quality piece of gear.
GL---Ernie VE3GNU

Alinco HF rigs don't seem to be as popular as the 'major players'---so my questions:  How do they compare with the rigs of the 'major players'?  How 'good' are they?  Price-wise they seem to offer 'good value' for what you get---heck, the newer models still offer true analog circuits (if I read the specs correctly)!  The Eham Reviews by owners are really 'all over the map'---so anyone?  What's been your experience?